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文章速递Purification of specularite by centrifugation instead of flotation to produce iron oxide red pigment 认领
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作者 Xi Zhang Shun-wei Zhu +3 位作者 Yu-jiang Li Yong-li Li Qiang Guo Tao Qi 《矿物冶金与材料学报:英文版》 SCIE EI CAS CSCD 2021年第1期56-65,共10页
This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation.An iron concentrate with a grade of 65.1 wt% and a recovery rate of 75.31% were obtained.A centrifug... This study used specularite, a high-gradient magnetic separation concentrate, as a raw material in reverse flotation.An iron concentrate with a grade of 65.1 wt% and a recovery rate of 75.31% were obtained.A centrifugal concentrator served as the deep purification equipment for the preparation of iron oxide red pigments, and its optimal rotating drum speed, feed concentration, and other conditions were determined.Under optimal conditions, a high-purity iron oxide concentrate with a grade of 69.38 wt% and a recovery rate of 80.89% were obtained and used as a raw material for preparing iron oxide red pigment.Calcining with sulfuric acid produced iron red pigments with different hues.Simultaneously, middlings with a grade of 60.20 wt% and a recovery rate of 17.51% were obtained and could be used in blast furnace ironmaking.High-value utilization of specularite beneficiation products was thus achieved. 展开更多
关键词 specularite reconcentration centrifugal concentrator iron oxide red pigment
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Transferrin receptor 1 plays an important role in muscle development and denervation-induced muscular atrophy 认领
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作者 Ying Li Juan-Xian Cheng +5 位作者 Hai-Hong Yang Li-Ping Chen Feng-Jiao Liu Yan Wu Ming Fan Hai-Tao Wu 《中国神经再生研究:英文版》 SCIE CAS 2021年第7期1308-1316,共9页
Previous studies demonstrate an accumulation of transferrin and transferrin receptor 1(TfR1) in regenerating peripheral nerves.However, the expression and function of transferrin and TfR1 in the denervated skeletal mu... Previous studies demonstrate an accumulation of transferrin and transferrin receptor 1(TfR1) in regenerating peripheral nerves.However, the expression and function of transferrin and TfR1 in the denervated skeletal muscle remain poorly understood.In this study, a mouse model of denervation was produced by complete tear of the left brachial plexus nerve.RNA-sequencing revealed that transferrin expression in the denervated skeletal muscle was upregulated, while TfR1 expression was downregulated.We also investigated the function of TfR1 during development and in adult skeletal muscles in mice with inducible deletion or loss of TfR1.The ablation of TfR1 in skeletal muscle in early development caused severe muscular atrophy and early death.In comparison, deletion of TfR1 in adult skeletal muscles did not affect survival or glucose metabolism, but caused skeletal muscle atrophy and motor functional impairment, similar to the muscular atrophy phenotype observed after denervation.These findings suggest that TfR1 plays an important role in muscle development and denervation-induced muscular atrophy.This study was approved by the Institutional Animal Care and Use Committee of Beijing Institute of Basic Medical Sciences, China(approval No.SYXK 2017-C023) on June 1, 2018. 展开更多
关键词 brachial plexus nerve INNERVATION iron motor dysfunction muscle atrophy signal skeletal muscle TRANSFERRIN
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Myricetin reduces cytotoxicity by suppressing hepcidin expression in MES23.5 cells 认领
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作者 Han Deng Shang Liu +2 位作者 Dong Pan Yi Jia Ze-Gang Ma 《中国神经再生研究:英文版》 SCIE CAS 2021年第6期1105-1110,共6页
Multiple studies implicate iron accumulation in the substantia nigra in the degeneration of dopaminergic neurons in Parkinson’s disease.Indeed,slowing of iron accumulation in cells has been identified as the key poin... Multiple studies implicate iron accumulation in the substantia nigra in the degeneration of dopaminergic neurons in Parkinson’s disease.Indeed,slowing of iron accumulation in cells has been identified as the key point for delaying and treating Parkinson’s disease.Myricetin reportedly plays an important role in anti-oxidation,anti-apoptosis,anti-inflammation,and iron chelation.However,the mechanism underlying its neuroprotection remains unclear.In the present study,MES23.5 cells were treated with 1×10^-6 M myricetin for 1 hour,followed by co-treatment with 400 nM rotenone for 24 hours to establish an in vitro cell model of Parkinson’s disease.Our results revealed that myricetin alleviated rotenone-induced decreases in cell viability,suppressed the production of intracellular reactive oxygen species,and restored mitochondrial transmembrane potential.In addition,myricetin significantly suppressed rotenone-induced hepcidin gene transcription and partly relieved rotenone-induced inhibition of ferroportin 1 mRNA and protein levels.Furthermore,myricetin inhibited rotenone-induced phosphorylation of STAT3 and SMAD1 in MES23.5 cells.These findings suggest that myricetin protected rotenone-treated MES23.5 cells by potently inhibiting hepcidin expression to prevent iron accumulation,and this effect was mediated by alteration of STAT3 and SMAD1 signaling pathways. 展开更多
关键词 factor flavonoid HEPCIDIN in vitro iron Parkinson’s disease PATHWAYS ROTENONE
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文章速递Single vs. Double Dose Iron Supplementation for Prevention of Iron Deficiency Anemia in Twin Pregnancy: A Randomized Controlled Clinical Trial 认领
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作者 Ahmed Mohammed Abbas Manal Mahmoud Elhalwagy +2 位作者 Khaled Afifi Khaled Ibrahim Mohamed Samir Sweed 《妇产科期刊(英文)》 2020年第12期1788-1802,共15页
<b><span style="font-family:Verdana;">Introduction: </span></b><span style="font-family:Verdana;">It is estimated that about 18% of pregnant women suffer from iron def... <b><span style="font-family:Verdana;">Introduction: </span></b><span style="font-family:Verdana;">It is estimated that about 18% of pregnant women suffer from iron deficiency anemia throughout their whole pregnancy.</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">In </span><span style="font-family:Verdana;">twin</span><span style="font-family:Verdana;"> pregnancy, owing to the relatively greater </span><span style="font-family:Verdana;">feto-placental</span><span style="font-family:Verdana;"> requirements and greater expansion in maternal plasma volume </span></span><span style="font-family:Verdana;">and red cell mass, iron requirements </span><span style="font-family:""><span style="font-family:Verdana;">are magnified 1.8 times compared to singleton pregnancies. However, for </span><span style="font-family:Verdana;">prevention</span><span style="font-family:Verdana;"> of iron deficiency in twin </span><span style="font-family:Verdana;">pregnancy</span><span style="font-family:Verdana;">, only sparse data exist regarding the sufficiency of the standard antenatal iron supplementation dose used in singleton pregnancies to meet the increased iron demand. In this study, we investigate the effect of single and double dose iron supplementation for </span><span style="font-family:Verdana;">prevention</span><span style="font-family:Verdana;"> of iron deficiency anemia in twin pregnancy. </span><b><span style="font-family:Verdana;">Methods: </span></b><span style="font-family:Verdana;">A randomized controlled clinical trial was conducted at our center in the period between February 2019 and October 2020,</span></span><span style="font-family:Verdana;"> and</span><span style="font-family:""> <span style="font-family:Verdana;">included</span><span style="font-family:Verdana;"> 450 eligible healthy non-anemic women aged 18 </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;"> 35 years, with twin pregnancy at 12 </span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;"> 16 weeks of gestation. After informed consent, eligible women were randomized to receive either single dose 27 mg, or double dose 54 mg elemental iron supplementation. Monitoring of hemoglobin concentration was done at fixed time points during gestation: at enrollment, 24 weeks, 32 weeks </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> before delivery. The primary outcome of the study was the incidence of iron deficiency anemia during </span><span style="font-family:Verdana;">follow up</span><span style="font-family:Verdana;"> until delivery. </span><b><span style="font-family:Verdana;">Results: </span></b><span style="font-family:Verdana;">The incidence of iron deficiency anemia in the two groups did not differ significantly between the </span><span style="font-family:Verdana;">single dose</span><span style="font-family:Verdana;"> group (19.1%) and the double dose group (24.0%). In women who did not develop Iron Deficiency Anemia, hemoglobin concentration varied significantly along the different gestational ages during the </span><span style="font-family:Verdana;">follow up</span><span style="font-family:Verdana;"> pe</span><span><span style="font-family:Verdana;">riod. In contrast, they did not show </span><span style="font-family:Verdana;">an overall statistically significant difference</span></span><span style="font-family:Verdana;"> in the hemoglobin concentrations between the single or double dose groups. </span><b><span style="font-family:Verdana;">Conclusion:</span></b> <span style="font-family:Verdana;">This</span><span style="font-family:Verdana;"> clinical trial did not demonstrate an added benefit for doubling prophylactic iron supplementation dose in non-anemic women with </span><span style="font-family:Verdana;">twin</span><span style="font-family:Verdana;"> pregnancy. 展开更多
关键词 Iron Supplementation Iron Deficiency Anemia Twin Pregnancy Hepcidin Mucosal Block
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A Novel Approach for Iron Deficiency Anaemia with Liposomal Iron: Concept to Clinic 认领
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作者 Manish Maladkar Srividya Sankar Ashok Yadav 《生物科学与医学(英文)》 2020年第9期27-41,共15页
Iron deficiency anaemia is the most common nutritional deficiency disorder, contributing to 50 percent of all the anaemias in the world. Dietary changes alone are insufficient for the correction and management of iron... Iron deficiency anaemia is the most common nutritional deficiency disorder, contributing to 50 percent of all the anaemias in the world. Dietary changes alone are insufficient for the correction and management of iron deficiency anaemia. Hence, iron supplementation is necessary. Conventional oral iron therapy is limited in many patients because of dose dependent side effects, insufficient absorption, lack of compliance and limitation in various inflammatory conditions. Liposomal iron is a technologically designed, innovative form of iron which due to its differential delivery system ensures higher absorption and bioavailability, greater tolerability and least gastro-intestinal side effects unlike conventional oral iron preparations. This review provides a critical discussion and a comprehensive view based on the author’s review of the medical literature concerning the technology of liposomal iron preparation, mechanism of its absorption, its advantage over conventional iron preparations and clinical evidence on its usage in iron deficient states in pregnancy and certain inflammatory conditions. 展开更多
关键词 Liposomal Iron Iron Deficiency ANAEMIA MICROENCAPSULATION Micronisation PREGNANCY Inflammation Chronic Kidney Disease
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Effect of Cu-Ni and Cu-Ni-Mn on the Microstructural and Mechanical Behaviour of As-Cast Non-Inoculated Hypereutectic Grey Iron 认领
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作者 Seidu Ojo Adama Sumaila Onigbajumo Adetunji 《矿物质和材料特性和工程(英文)》 2020年第2期27-46,共20页
The hypereutectic region of grey cast iron has received very little attention especially for designing cast products by researchers. Due to its high carbon equivalence, hypereutectic grey iron poses some challenges es... The hypereutectic region of grey cast iron has received very little attention especially for designing cast products by researchers. Due to its high carbon equivalence, hypereutectic grey iron poses some challenges especially its tendency for grey to white transition (GWT) at this level of carbon content. However, hypereutectic grey iron possesses inherent properties that could be easily utilized for improved performance in automobile engines and brake pad system. Significantly, they could be modified for superior hardness, strength and toughness. This study presents the effect of microalloying on the mechanical behaviour of hypereutectic grey cast iron with carbon equivalence above 4.5. The first part of this work presented in this paper considers the addition of Cu-Ni and Cu-Ni-Mn to series of as-cast hypereutectic grey cast iron and their hardness and tensile strength were studied and compared. A total of 33 cast samples were obtained with the control sample. The examination of the micrographs revealed that graphite eutectics cells of Type A and A + D were obtained in the resulting microstructure. Results analyses showed that the ferrite forming tendency of silicon was suppressed due to the high carbon content of the as-cast hypereutectic grey iron coupled with the absence of inoculation which plays a great role in the graphite flake type, network, size and distribution. Cu-Ni microalloying was also confirmed to promote hardness with the hardening effect limit of nickel observed at 1.3% composition. For Cu-Mi-Mn addition, excess and free sulphur in the hyper- eutectic grey iron results in reverse effect of manganese on strength, hardness, reduced graphite flake size and shape. 展开更多
关键词 HYPEREUTECTIC Grey IRON Microstructure Hardness Tensile Strength Inoculation GRAPHITIZATION Cast IRON Alloying
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Evidences by Multiscale Analysis and 2D3/4 Models from the Magnetic Anomalies and Iron Mineralization (BIF) over the DJADOM-ETA Area, Southeastern Cameroon 认领
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作者 Justine Yandjimain Théophile Ndougsa-Mbarga +1 位作者 Arsène Meying Paul Claude Ngoumou 《地震研究(英文)》 2020年第1期19-32,共14页
The Magnetic method is one of the best geophysical techniques used to delineate subsurface structures. This study was conducted to investigate the basement faulting and ore mineralization into the overlying geological... The Magnetic method is one of the best geophysical techniques used to delineate subsurface structures. This study was conducted to investigate the basement faulting and ore mineralization into the overlying geological cover. The GEOSOFT v8.4 software was used to process the data. Upward continuation of the residual magnetic intensity map at various altitudes and the maxima of their horizontal gradient magnetic were used to highlight faults from shallow to deep, as well as, their dips and mineralization zones. The faults with the directions E-W, ESE-WNW and ENE-WSW are identified confirming the result of [1]. This study also reveals that, the layer is affected by faults propagating from the basement upwards into the cover. Our results added additional information to the knowledge of the geological structure and the mineral resources potential in the study area. Based on the 2D3/4 modeling, the Dja Fault (DF) is revealed and highlighted sub-area marked by a magnetite/or hematite dolerite, schist and sandstone blocks, which show strong magnetization. Specifically, in this area, models are made of BIF (bounded iron formation) and BIQ (bounded iron quartzite) as dominant minerals. 展开更多
关键词 AEROMAGNETIC Anomalies Multiscale Mineralization (BIF (Bounded IRON Formation) BIQ (Bounded IRON Quartzite)) HMG (Horizontal Gradient Magnetic) Faults
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The Prospects of Uganda’s Iron Ore Deposits in Developing the Iron and Steel Industry 认领
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作者 Muwanguzi J. B. Abraham Rukenzo Gift +4 位作者 Sebukeera Hennery Guloba Asuman Ajidiru Rita Dumba Dexter Muvawala Joseph 《矿物质和材料特性和工程(英文)》 2020年第4期316-329,共14页
Uganda aspires to exploit its abundant iron ore resources to supply the required raw material for developing its iron and steel industry across all the phases of the value chain. The country imports USD 369 million wo... Uganda aspires to exploit its abundant iron ore resources to supply the required raw material for developing its iron and steel industry across all the phases of the value chain. The country imports USD 369 million worth of iron and steel products annually, 60% of which are raw materials for the steel processing plants. The National Planning Authority, the government planning agency, undertook a study to assess the possibility of using the iron ore deposits available in the country, as a source of supply for iron and steel production. In the study, available geological literature was collected from various sources and analysed in order to understand the mode of iron ore mineralization in Uganda, particularly, that in the South West. A field excursion to the deposits was conducted in order to ground truth the information obtained from literature research;carry out a detailed reconnaissance study so as to benchmark the likely scenarios required in the development of the iron and steel value chain;and establish the likely mining and processing requirements of the deposits. The reconnaissance survey confirmed the existence of hematite deposits that visually show characteristics of high-quality iron ore (55% - 68% Fe) suitable for iron production. From surficial investigations, the deposits are mainly comprised of thin beds of mineralisation. The deposits occur in the form of massive hematite, which is amenable to mining and direct feed to the ore processing plants, and specularite hematite (a metamorphic platy variety), which normally requires mineral processing for amenability to reduction processes. From the analysis, the country has sufficient deposits of a high grade that can support a steel industry, though more detailed quantifications and characterisations need to be prioritised by the government. 展开更多
关键词 MINERALIZATION Iron Ore Iron Steel GEOLOGY NPA Uganda
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Natural Iron Chelators: An Orthomolecular Approach to Treat Iron Overload and Its Related Diseases 认领
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作者 Asmae Mesbahi El Aouame Karima El Akkaly Ilyes Baghli 《食品科学与工程:英文版(美国)》 2020年第1期28-32,共5页
Despite its various vital roles in the different body’s metabolisms,iron may have a hazardous impact on health when it exceeds its normal values.Iron overload is triggered by many genetic and behavioral factors.Furth... Despite its various vital roles in the different body’s metabolisms,iron may have a hazardous impact on health when it exceeds its normal values.Iron overload is triggered by many genetic and behavioral factors.Furthermore,excessive iron levels have also been observed in many pathologies such as Alzheimer’s,Parkinson’s,cardiovascular and some cancerous diseases.This paper describes a set of natural iron chelators as an effective and a safe orthomolecular approach in chelating iron.Orthomolecular medicine is based on providing patients with nutritional supplementation at high doses to treat and prevent diseases.This paper describes the properties of a set of flavonoids and phenolic acids such as curcumin and ferulic acid that can be administered as supplements to patients suffering from iron overload since they are classified as strong chelators.Those natural iron chelators’supplements are mainly extracted from fruits,vegetables,and plants.As chelators,they are able to bind effectively to iron,inhibit the production of reactive oxygen species,and reduce the levels of oxidative stress.They can also play an effective therapeutic role in the treatment of neurodegenerative,cardiovascular,diabetic,and cancerous diseases thanks to their iron chelation,antioxidant,and anti-inflammatory properties. 展开更多
关键词 IRON natural iron chelators iron overload FLAVONOIDS phenolic acids neurodegenerative diseases cancerous diseases orthomolecular medicine
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Thermal conductivity of cast iron-A review 认领
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作者 Guang-hua Wang Yan-xiang Li 《中国铸造:英文版》 SCIE 2020年第2期85-95,共11页
This paper gives a brief introduction to the four research methods for the study on thermal conductivity of cast irons,including experimental measurement,statistical analysis,effective medium theory and numerical simu... This paper gives a brief introduction to the four research methods for the study on thermal conductivity of cast irons,including experimental measurement,statistical analysis,effective medium theory and numerical simulation.Recent studies on the thermal conductivity of various cast irons are reviewed through the influence of alloying elements,structural constituents,and temperature.The addition of alloying elements is the main reason that restricts the thermal conductivity of cast irons,especially spheroidal graphite cast iron.The connectivity of graphite has a significant effect on the thermal conductivity of flake and compacted graphite cast irons,semiquantitative and quantitative analysis of this factor is a key and difficult point in the study of thermal conductivity of cast irons.The thermal conductivities of different types of cast irons show varying degrees of dependence on temperature.This phenomenon is the combination of graphite and matrix,rather than just depending on graphite morphology.The study of the relationship between individual phase and temperature is the focus of future research.These summaries and discussions may provide reference and guidance for the future research and development of high thermal conductivity cast irons. 展开更多
关键词 CAST IRON thermal conductivity GRAY CAST IRON NODULAR castiron COMPACTED graphite CAST IRON
文章速递Haematopoietic Effects of Amloki (<i>Emblica officinalis</i>) in Pregnancy with Iron Deficiency Anaemia 认领
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作者 Tahmina Akter Qazi Shamima Akhter +7 位作者 Md. Shah Amran Saima Haque Lisa Ariza Sultana Farhana Sultana Rahnuma Ahmad Sayeda Tasnim Kamal Tamanna Binte Habib Farhana Rahman 《生物科学与医学(英文)》 2020年第12期157-165,共9页
Due to poverty and ignorance more than half of the pregnant women in developing country are suffering from iron deficiency anaemia (IDA). Different gastrointestinal side effects cause low compliance to iron supplement... Due to poverty and ignorance more than half of the pregnant women in developing country are suffering from iron deficiency anaemia (IDA). Different gastrointestinal side effects cause low compliance to iron supplementation. Amloki (<em>Emblica officinalis</em>) is very popular among pregnant women for its taste and traditional belief of well-being. The aim of this study is to determine the effects of amloki on RBC, WBC and Platelet count. Prospective comparative study was carried out on patients of Outpatient Department of Obstetrics and Gynecology, Dhaka Medical College Hospital from July 2016 to June 2017. A total of 43 pregnant women between the 13th to the 20th weeks of gestation with IDA were selected aged 18 - 36 years in this study. Anemic pregnant women supplemented with oral iron and amloki were considered as study group (A) and control group (B) were with only iron supplementation for 45 days. Total count of RBC, WBC and platelet were done in the Department of Hematology & BMT Unit, Dhaka Medical College Hospital, Dhaka. For statistical analysis, Paired Student’s “t” test and Unpaired Student’s “t” test were considered using SPSS 22.0 version. A significant increase (p < 0.05) of blood RBC count was observed after intervention of iron in both groups. There was also significant increase in RBC count in iron + amloki supplemented group than that of only iron supplemented group. In this study, there was also increase of WBC count in iron + amloki supplemented group and decrease of platelet count in both groups, but these changes were not statistically significant. It can be concluded that oral amloki supplementation causes increased blood RBC count in IDA with pregnancy. 展开更多
关键词 Iron Deficiency Anaemia Pregnancy Amloki RED Blood Cell White Blood Cell Platelet
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Appropriate Location and Deployment Method for Successful Iron Fertilization 认领
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作者 Tai-Jin Kim 《海洋科学期刊(英文)》 2020年第3期149-172,共24页
“High nutrient, low chlorophyll (HNLC)” regions were created by locking iron into sedimentary iron sulfides with hydrogen sulfide available from volcanic eruptions in surrounding oceans. Appropriate locations and de... “High nutrient, low chlorophyll (HNLC)” regions were created by locking iron into sedimentary iron sulfides with hydrogen sulfide available from volcanic eruptions in surrounding oceans. Appropriate locations and deployment methods for the iron fertilization were far from volcanoes, earthquakes and boundaries of tectonic plates to reduce the chance of iron-locking by volcanic sulfur compounds. The appropriate locations for the large-scale iron fertilization are proposed as Shag Rocks in South Georgia and the Bransfield Strait in Drake Passage in the Southern Ocean due to their high momentum flux causing efficient iron deployment. The iron (Fe) replete compounds, consisting of natural clay, volcanic ash, agar, N</span><sub><span style="font-size:12px;font-family:Verdana;">2</span></sub><span style="font-size:12px;font-family:Verdana;">-fixing mucilaginous cyanobacteria, carbon black, biodegradable plastic foamed polylactic acid, fine wood chip, and iron-reducing marine bacterium, are deployed in the ocean to stay within a surface depth of 100</span></span></span><span><span><span style="font-family:""> </span></span></span><span style="font-size:12px;font-family:Verdana;"><span style="font-size:12px;font-family:Verdana;"><span style="font-family:Verdana;font-size:12px;">m for phytoplankton digestion. The deployment method of Fe-replete composite with a duration of at least several years for the successful iron fertilization, is configured to be on the streamline of the Antarctic Circumpolar Current (ACC). This will result in high momentum flux for its efficient dispersion on the ocean surface where diatom, copepods, krill and humpback whale stay together (~100</span></span></span><span><span><span style="font-family:""> </span></span></span><span><span><span style="font-family:""><span style="font-size:12px;font-family:Verdana;">m). Humpback whales are proposed as a biomarker for the successful iron fertilization in large-scale since humpback whales feed on krill, which in turn feed on cockpods and diatoms. Th 展开更多
关键词 Appropriate Location Deployment Method Iron Fertilization Volcanic Sulfur Compounds Humpback Whale
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Effects of iron precursors on the structure and catalytic performance of iron molybdate prepared by mechanochemical route for methanol to formaldehyde 认领
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作者 Lingtao Kong Shengtao Xu +3 位作者 Xue Liu Chaofan Liu Dandan Zhang Ling Zhao 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2020年第6期1603-1611,共9页
Mechanochemical synthesis has been applied for many novel material preparations and gained more and more attention due to green and high-efficiency recently. In order to explore the influences of iron precursors on st... Mechanochemical synthesis has been applied for many novel material preparations and gained more and more attention due to green and high-efficiency recently. In order to explore the influences of iron precursors on structure and performance of iron molybdate catalyst prepared by mechanochemical route, three typical and cheap iron precursors have been used in preparation of iron molybdate catalyst. Many characterization methods have been employed to obtain the physical and chemical properties of iron molybdate catalyst. Results indicate that iron precursors have the significant impact on the phase composition, crystal morphology and catalytic performance in the conversion of methanol to formaldehyde. It is hard to regulate the phase composition by changing Mo/Fe mole ratios for Fe2(SO4)3 as iron precursor. In addition, as for Fe2(SO4)3, the formaldehyde yield is lower than that from iron molybdate catalyst prepared with Fe(NO3)3·9H2O due to the reduction in Fe2(MoO4)3 phase as active phase. Based on mechanochemical and coprecipitation method, the solvent water could be a key factor for the formation of MoO3 and Fe2(MoO4) for FeCl3·6H2O and Fe2(SO4)3 as precursors. Iron molybdate catalyst prepared with Fe(NO3)3·9H2O by mechanochemical route, shows the best methanol conversion and formaldehyde yield in this reaction. 展开更多
关键词 Iron precursors Mechanochemical route Iron molybdate catalyst Methanol oxidation
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Influence of Potassium Nutrition and Exogenous Organic Acids on Iron Uptake by Monocot and Dicot Plants 认领
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作者 Eman F. A. Awad-Allah Ibrahim H. Elsokkary 《土壤科学期刊(英文)》 2020年第10期486-500,共15页
Iron (Fe) is a vital element for the survival and proliferation of all plants;therefore, Fe-biofortification by the application of chemical and organic fertilizers is being as an effective approach to fight hidden hun... Iron (Fe) is a vital element for the survival and proliferation of all plants;therefore, Fe-biofortification by the application of chemical and organic fertilizers is being as an effective approach to fight hidden hunger retards the growth and development of crop plants. Two experiments were carried out to investigate the effect of potassium and exogenous organic acids on iron uptake by two different plants<span>:</span><span> one is monocotyledon</span><span>,</span><span><span> maize (<i></i></span><i><i><span>Zea mays</span></i><span></span></i> L.) and the second is dicotolydon pea (<i></i></span><i><i><span>Pisum sativum</span></i></i><span> L.) grown under controlled conditions. The seedlings were grown in sand culture in a greenhouse experiment and irrigated with one-tenth strength modified nutrient solution of Hoagland and Arnon as a base solution (pH 7.5), containing different iron treatments (0, 1, and 5 ppm as FeSO</span><sub>4</sub>·<span>7H</span><sub><span>2</span></sub><span>O) combined with potassium nutrition (0, 5, 10, and 50 ppm as K</span><sub><span>2</span></sub><span>SO</span><sub><span>4</span></sub><span>). After 30 days, the best interaction treatment was selected for further experiment including 5.0 ppm Fe as FeSO</span><sub>4</sub><sup>.</sup><span>7H</span><sub><span>2</span></sub><span>O and 50 ppm K as K</span><sub><span>2</span></sub><span>SO</span><sub><span>4</span></sub><span> in combination with 1</span><span> </span><span>×</span><span> </span><span><span>10<sup>-</sup></span><sup><span>5</span></sup><span> mole/liter of one </span></span><span>of </span><span>the following organic acids: Citric acid, Oxalic acid, Formic acid, Acetic acid, Propionic acid, Tartaric acid, Succinic acid, Fumaric acid, Malic acid, Glutamic acid, besides the free organic acid nutrient solution as a control. Results revealed that the interaction between 5.0 ppm Fe and 50 ppm K was the best interaction treatment for increasing biomass production and iron uptake of maize and pea seedlings under appli 展开更多
关键词 POTASSIUM Organic Acids Iron Uptake BIOFORTIFICATION SUSTAINABILITY
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Longitudinal Study of Iron Deposition and Volume in the Precentral Gyrus in Patients with Relapse-Remitting Multiple Sclerosis 认领
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作者 Silin Du Chun Zeng Zhiwei Zhang 《生物科学与医学(英文)》 2020年第5期84-95,共12页
Objective: To longitudinally assess dynamic changes of iron deposition and volume of the precentral gyrus and its correlation with clinical manifestations of Relapse-Remitting Multiple Sclerosis(RRMS) by using 3D enha... Objective: To longitudinally assess dynamic changes of iron deposition and volume of the precentral gyrus and its correlation with clinical manifestations of Relapse-Remitting Multiple Sclerosis(RRMS) by using 3D enhanced T2* weighted angiography(ESWAN). Methods: Thirty RRMS patients and thirty age- and sex-matched healthy controls were recruited and underwent ESWAN and 3D T1WI twice interval of one year with the same parameters. The mean phase values (MPVs) and volumes in precentral gyrus gray matter (PGM) were measured, and change of iron content and its correlation with volume, clinical manifestations were analyzed. Results: Compared with controls, the RRMS had higher iron deposition in both single-time measurements, but the volume decreased. Comparing to the first scan, we found significant difference in MPVs between the two times (P rs = 0.764, P rs = 0.592, P rs = 0.582, P rs = -0.399, P rs = -0.745, P rs = -0.367, P Conclusions: With the disease progression, the content of iron in PGM in RRMS patients is increasing, while the volume has no obvious change, suggesting that the iron deposition may precede or develop faster than cerebral atrophy. 展开更多
关键词 Relapse-Remitting Multiple SCLEROSIS Precentral GYRUS IRON BRAIN ATROPHY
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Pilot Test of the Permeable Reactive Barrier for Removing Uranium from the Flooded Gunnar Pit 认领
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作者 Dexu Kong Lesley McGilp +2 位作者 Alexey Klyashtorin Ian Wilson Lee D. Wilson 《地球科学和环境保护期刊(英文)》 2020年第7期155-176,共22页
This work reports on applying iron oxide coated sand (IOCS) media in an experimental permeable reactive barrier to remove uranium (U) species from uranium containing water. A field study was conducted at the legacy Gu... This work reports on applying iron oxide coated sand (IOCS) media in an experimental permeable reactive barrier to remove uranium (U) species from uranium containing water. A field study was conducted at the legacy Gunnar uranium mine & mill site that was abandoned in the 1960s with limited to no decommissioning. The flooded Gunnar mine pit presently contains about 3.2 million m<sup>3</sup> of water contaminated by dissolved U (1.2 mg/L), Ra-226 (0.4 Bq/L), and minor concentrations of other contaminants (As, Se, etc.). The water is seeping over the pit rim into Lake Athabasca, posing potential environmental and health concerns. IOCS media can be used to immobilize uranium species through an adsorption process. Herein, the preparation of hydrous ferric oxide sorbents and their supported forms onto silica sands is described. Fourier transform infrared spectroscopy (FTIR) and powder X-ray diffraction (pXRD) were used for structural characterization. The adsorption properties of the IOCS sorbent media were modeled by the Langmuir adsorption isotherm, where a maximum uranium uptake capacity was estimated. Bench-scale adsorption kinetic experiments were also performed before moving to a field trial. Based on these lab results and input on field-scale parameters, a pilot permeable reactive barrier was fabricated and a field test conducted near the Gunnar pit in June 2019. This pilot test provided technical data and information needed for designing a full-scale permeable barrier that employs the IOCS media. This approach can be applied for in-situ water treatment at Gunnar and other legacy uranium sites. 展开更多
关键词 ADSORPTION BREAKTHROUGH Iron Oxide Coated Sand Permeable Reactive Barrier Uranium Species
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γ⁃Fe2O3@carboxymethyl Cellulose as Potential Oral Nanomedicine for Iron Deficiency Anemia Treatment on Rats 认领
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作者 Bo Chen Peng Zhao +6 位作者 Qiwei Wang Zhanhang Guo Xin Liu Yan Li Yue Zhang Min Ji Ning Gu 《哈尔滨工业大学学报:英文版》 EI CAS 2020年第3期158-169,共12页
Oral iron supplements such as ferrous iron salts are major treatment agents for iron deficiency anemia(IDA)due to the convenience of large dose administration and good patient compliance.However,the gastrointestinal a... Oral iron supplements such as ferrous iron salts are major treatment agents for iron deficiency anemia(IDA)due to the convenience of large dose administration and good patient compliance.However,the gastrointestinal adverse impact caused by Fe2+stimulus and low bioavailability severely impedes its therapeutic effects.In recent years,it has been found that nano iron⁃based nanoparticles with high surface⁃to⁃volume ratio and low iron ion leakage can alleviate the toxic effect and improve the gastrointestinal absorbance.For further clinical development,nano materials need to meet the pharmaceutical quality demand.Carboxymethyl cellulose(CMC)is a significant pharmaceutical ingredient applied in approved drug formulations,and polyglucosorbitol carboxymethylether(PSC)has been utilized in iron⁃based nanomedicine ferumoxytol synthesis,both of which can be firmly anchored on iron oxide by carboxyl chelation.In this work,iron oxide nanoparticles(NPs)modified with CMC were designed and synthesized,and the structure composition and physicochemical properties were distinctly characterized.Oral supplement effects on rat IDA were investigated and compared with other recently reported iron supplements including NPs modified with PSC.Results show that the oral nano iron supplement achieved the recovery of hemoglobin and serum iron level in only two weeks with high safety.The nano iron oxide modified with pharmaceutical excipients provides new potential approach for oral iron supplement available in clinics. 展开更多
关键词 iron oxide nanomedicine carboxymethyl cellulose polyglucosorbitol carboxymethylether oral agent iron deficiency anemia
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Genotypic Variation in Spatial Distribution of Fe in Rice Grains in Relation to Phytic Acid Content and Ferritin Gene Expression 认领
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作者 Anurag MISHRA MdSHAMIM +3 位作者 MdWASIM Siddiqui Akanksha SINGH Deepti SRIVASTAVA K.N.SINGH 《水稻科学:英文版》 SCIE CSCD 2020年第3期227-236,共10页
Rice varieties having high Fe concentration in the endospermic region can be used as a good source for Fe deficit population.In this study,303 Oryza sativa varieties and 1 Oryza rufipogon accession were assessed for s... Rice varieties having high Fe concentration in the endospermic region can be used as a good source for Fe deficit population.In this study,303 Oryza sativa varieties and 1 Oryza rufipogon accession were assessed for spatial Fe accumulation in grains by Prussian blue staining method.Spatial ferritin protein distribution in grains was visualized by immunohistochemistry,and ferritin expression was assessed in selected rice varieties using semi-quantitative reverse transcription PCR.Three popular rice varieties,namely Sarjoo 52,Madhukar and Jalmagna,and the O.rufipogon variety showed Fe in all the regions of grains,and the highest Fe concentration was observed in the embryo region.Some high-yielding varieties like Swarna,Swarna Sub 1,CSR13 and NDRR359 had lower Fe concentration in the embryo region.The highest Fe concentration was detected in O.rufipogon(49.8μg/g),followed by Sarjoo 52(26.1μg/g)and Madhukar(25.7μg/g).Phytic acid concentration was the minimum in O.rufipogon(5.75 mg/g)followed by Sarjoo 52(5.83 mg/g).Western blot and semi-quantitative reverse transcription PCR showed higher expression of ferritin gene in O.rufipogon,Sarjoo 52 and Madhukar.In conclusion,O.rufipogon and Sarjoo 52 had higher Fe concentration in the embryo regions as well as endosperm and aleurone layer,whereas the other varieties had lower Fe concentration in the endosperm.Sarjoo 52 could be used as a donor in the rice breeding program for the generation of new varieties with elevated grain Fe concentration. 展开更多
关键词 bio-fortification IRON accumulation FERRITIN TISSUE-SPECIFIC localization IRON DEFICIT population
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硅铁施用对水稻生长及磷吸收的影响 认领
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作者 刘煜椿 李仁英 +6 位作者 谢晓金 李霖 徐向华 张婍 吴思佳 简静 李玉聪 《农业资源与环境学报》 CAS 北大核心 2020年第4期511-517,共7页
为探讨硅铁施用对水稻生长和磷吸收的影响,指导合理施肥、提高磷素利用率,利用水培试验研究了不同浓度铁(0、0.5、1、2 mmol·L^-1)预处理下施加不同浓度硅(0、1、4 mmol·L^-1)对水稻生长及磷吸收的影响。结果表明,低浓度的铁... 为探讨硅铁施用对水稻生长和磷吸收的影响,指导合理施肥、提高磷素利用率,利用水培试验研究了不同浓度铁(0、0.5、1、2 mmol·L^-1)预处理下施加不同浓度硅(0、1、4 mmol·L^-1)对水稻生长及磷吸收的影响。结果表明,低浓度的铁预处理对水稻SPAD、株高、根长和地上部干质量无显著影响,而高浓度的铁预处理下,这些指标则显著降低(P<0.05)。中低浓度铁处理下施硅在一定程度上增加了水稻株高、根长和地上部干质量,但未达到显著水平(P>0.05)。铁预处理显著增加了水稻根表铁膜的厚度及根表铁膜中的磷含量(P<0.05),施硅则显著降低了0.5 mmol·L^-1和1 mmol·L^-1铁预处理的水稻根表铁膜的厚度(P<0.05)。铁预处理对水稻根部的磷含量无显著影响,但显著降低了地上部磷的含量(P<0.05)。施硅对水稻根和地上部的磷含量无显著影响。研究表明,施铁处理显著诱导了根表铁膜的出现,增加了铁膜中的磷含量并且显著降低了地上部的磷含量;施硅在一定程度上缓解了水稻生长中的铁毒害现象,并且能够改变根表铁膜厚度,减少根冠比,从而影响水稻磷的吸收转运。 展开更多
关键词 铁膜 水稻
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Microstructural analysis of EN-GJS-450-10 ductile cast iron via vibrational casting 认领
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作者 Caglar Yüksel 《中国铸造:英文版》 SCIE 2020年第4期272-278,共7页
EN-GJS-450-10 ductile cast iron was produced with and without vibration to evaluate microstructural features. To investigate the effect of vibration, a reference, and two different castings having amplitudes of 0.9 mm... EN-GJS-450-10 ductile cast iron was produced with and without vibration to evaluate microstructural features. To investigate the effect of vibration, a reference, and two different castings having amplitudes of 0.9 mm and 1.8 mm were cast with a fixed vibration frequency of 50 Hz. The nodule count (density), form (type), size distribution, nodularity, and the fraction of graphite, percentages of both ferrite and pearlite phases, length of ferrite shell, and pore, were evaluated via optical microscopy using an image analysis software. It is observed that the microstructure of the cast iron is more uniform by vibrational casting than that by non-vibrational casting. Additionally, mechanical vibration enhances nodule count and nodularity, also, more ferritic matrix could be obtained after the application of vibration. Nodule count and nodularity of vibrational casting with 1.8 mm amplitude increased from 226 nodule per mm2 and 80% to 311 nodule per mm2 and 86.5% of non-vibrational casting. Percentages of ferrite and graphite area dramatically improved from 24% and 16.5% for non-vibrational casting to 57% and 22.3% for vibrational casting with 1.8 mm amplitude, whereas the percentages of pearlite and pores decreased significantly from 56.1% and 5% to 20% and 1%, respectively. 展开更多
关键词 mechanical vibration spheroidal cast iron ductile iron NODULARITY image analysis AMPLITUDE
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