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Technology of Eliminating White Smoke from Flue Gas 预览
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作者 Ping ZHAO Jinghai TAN +1 位作者 Minghao WANG Hongliang BAO 《气象与环境研究:英文版》 CAS 2020年第1期66-69,共4页
Based on the corresponding relationship chart of saturation humidity and temperature of wet flue gas,the formation mechanism of"white smoke plume"and the technology of eliminating white smoke from flue gas w... Based on the corresponding relationship chart of saturation humidity and temperature of wet flue gas,the formation mechanism of"white smoke plume"and the technology of eliminating white smoke from flue gas were analyzed.Besides,the energy balance of each elimination technology was calculated according to the theoretical formulas,and"energy saving"was compared.The technology of eliminating white smoke from flue gas needs to solve the problems of"emission reduction"and"energy conservation"in industrial enterprises.It brings new ideas and directions to enterprises for"energy conservation and emission reduction",eases the pressure on enterprises to protect the environment,improves enterprises'use efficiency of primary energy,and provides a reliable choice for enterprises to survive and enhance their competitiveness.In addition,it can effectively solve the dehumidification and elimination of wet flue gas,not only eliminate the pollution from white smoke plume,but also achieve environmental protection up-to-standard and ultra-low near zero emission at low cost,enhance the efficiency of coal combustion,in particular recover the moisture and residual heat in flue gas,and solve the contradiction between the environment and development. 展开更多
关键词 Elimination of white smoke Emission reduction Energy conservation White wet smoke plume Energy Environment
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Can the wet suction technique change the efficacy of endoscopic ultrasound-guided fine-needle aspiration for diagnosing autoimmune pancreatitis type 1? A prospective single-arm study 预览
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作者 Mitsuru Sugimoto Tadayuki Takagi +13 位作者 Rei Suzuki Naoki Konno Hiroyuki Asama Yuki Sato Hiroki Irie Ko Watanabe Jun Nakamura Hitomi Kikuchi Mika Takasumi Minami Hashimoto Tsunetaka Kato Takuto Hikichi Kenji Notohara Hiromasa Ohira 《世界临床病例杂志》 2020年第1期88-96,共9页
BACKGROUND Other than surgery,endoscopic ultrasound-guided fine-needle aspiration(EUSFNA)is the only procedure for histologically diagnosing autoimmune pancreatitis(AIP).However,adequate specimens are difficult to obt... BACKGROUND Other than surgery,endoscopic ultrasound-guided fine-needle aspiration(EUSFNA)is the only procedure for histologically diagnosing autoimmune pancreatitis(AIP).However,adequate specimens are difficult to obtain.Recently,more adequate specimens were reported to be obtained with EUS-FNA with a wet suction technique(WEST)than with conventional EUS-FNA.AIM To histologically diagnose AIP by EUS-FNA with a WEST.METHODS Eleven patients with possible type 1 AIP between February 2016 and August 2018 underwent EUS-FNA with a WEST(WEST group),with four punctures by 19 or 22 G needles.As a historical control,23 type 1 AIP patients who underwent no fewer than four punctures with 19 or 22 G needles were enrolled(DRY group).Patient characteristics and histological findings were compared between the two groups.RESULTS Three histopathological factors according to the International Consensus Diagnostic Criteria were significantly greater in the WEST group than the DRY group[lymphoplasmacytic infiltrate without granulocytic infiltration:9(81.8%)vs 6(26.1%),P=0.003,storiform fibrosis:5(45.5%)vs 1(4.3%),P=0.008,abundant(>10 cells/HPF)IgG4-positive cells:7(63.6%)vs 5(21.7%),P=0.026].Level 1 or level 2 histopathological findings were observed more often in the WEST group than in the DRY group[8(72.7%)vs 3(13.0%),P=0.001].CONCLUSION EUS-FNA with a WEST was more successful than standard EUS-FNA in histologically diagnosing AIP. 展开更多
关键词 Autoimmune pancreatitis Endoscopic ultrasound-guided fine needle aspiration Wet suction technique
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Experimental Study on Performance of a Closed Wet Cooling Tower for Air Wet-Bulb Temperature near 0℃
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作者 ZHOU Yasu ZHANG Pan +2 位作者 ZHAO Jingde YANG Honghai BAI Yufeng 《热科学学报:英文版》 SCIE EI CAS CSCD 2019年第5期1015-1023,共9页
Closed wet cooling towers(CWCTs) are used widely because of their better water quality and smaller water consumption. However, the operating parameters shown in the technical documents are only for rated conditions in... Closed wet cooling towers(CWCTs) are used widely because of their better water quality and smaller water consumption. However, the operating parameters shown in the technical documents are only for rated conditions in summer, not for any other conditions, especially in low air wet-bulb temperature areas such as those near 0℃. In addition, CWCTs often fail to achieve the designed cooling effect at low air wet-bulb temperatures. A experiment set of CWCT was built, and the performance of the CWCT at low air wet-bulb temperature near 0℃ was investigated. The impact of the operating parameters(air flow rate, cooling water flow rate, and spray water flow rate) on the heat and mass transfer performance of the CWCT was measured and analyzed. The results show the cooling performance of the CWCT at an air wet-bulb temperature 0℃, 2℃, and 4℃ is about 47%–63% of the rated operating condition;the optimal operating parameters of these conditions for the CWCT are just the same as those of the rated operating condition in summer. According to the experimental results, some operating advices are given. 展开更多
关键词 CLOSED wet COOLING TOWER performance of COOLING TOWER low AIR WET-BULB TEMPERATURE rated operating parameters evaluation index
Drag Characteristics Prediction for Wet Multi-Disk Brakes 预览
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作者 Tianhong Luo Zhongtao Li Fuying Li 《北京理工大学学报:英文版》 EI CAS 2019年第3期549-560,共12页
To improve the characteristics of wet multi-disc brakes (WMDBs), the WMDBs of the drive axles of mining trucks were studied. A model was established to predict the phenomenon of drag characteristics during wet brake n... To improve the characteristics of wet multi-disc brakes (WMDBs), the WMDBs of the drive axles of mining trucks were studied. A model was established to predict the phenomenon of drag characteristics during wet brake non-engagement by considering the combined effect of surface grooves, film shrinkage, and laminar Navier-Stokes (N-S) equations. The model was used to study drag torque and temperature variation of the wet brakes for different volume flows, dynamic viscosities, and friction pair clearances. The simulation results indicated that the peak torque decreased when the clearance of the friction pair increased. Additionally, the peak torque increased when the volume flow increased and when the cooling liquid dynamic viscosity increased. The model was more accurate than a traditional forecasting system when considering the role of surface grooves and oil film shrinkage in actual working conditions. 展开更多
关键词 WET BRAKE drag TORQUE combined effects MULTI-PARAMETER PREDICTION system
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Etching‐assisted femtosecond laser modification of hard materials 预览
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作者 Xue-Qing Liu Ben-Feng Bai +1 位作者 Qi-Dai Chen Hong-Bo Sun 《光电进展(英文)》 2019年第9期1-14,共14页
With high hardness, high thermal and chemical stability and excellent optical performance, hard materials exhibit great potential applications in various fields, especially in harsh conditions. Femtosecond laser ablat... With high hardness, high thermal and chemical stability and excellent optical performance, hard materials exhibit great potential applications in various fields, especially in harsh conditions. Femtosecond laser ablation has the capability to fabricate three-dimensional micro/nanostructures in hard materials. However, the low efficiency, low precision and high surface roughness are the main stumbling blocks for femtosecond laser processing of hard materials. So far, etching- assisted femtosecond laser modification has demonstrated to be the efficient strategy to solve the above problems when processing hard materials, including wet etching and dry etching. In this review, femtosecond laser modification that would influence the etching selectivity is introduced. The fundamental and recent applications of the two kinds of etching assisted femtosecond laser modification technologies are summarized. In addition, the challenges and application prospects of these technologies are discussed. 展开更多
关键词 FEMTOSECOND laser HARD materials WET ETCHING DRY ETCHING
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A scalable synthesis of silicon nanoparticles as high-performance anode material for lithium-ion batteries
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作者 Jin Li Juan-Yu Yang +1 位作者 Jian-Tao Wang Shi-Gang Lu 《稀有金属:英文版》 SCIE EI CAS CSCD 2019年第3期199-205,共7页
In this work, a scalable and cost-effective method including mechanical milling, centrifugation and spray drying was developed to fabricate Si nanoparticles.The synthesized Si nanoparticles show an average size of 62 ... In this work, a scalable and cost-effective method including mechanical milling, centrifugation and spray drying was developed to fabricate Si nanoparticles.The synthesized Si nanoparticles show an average size of 62 nm and exhibit a narrow particle size distribution. The influence of particle sizes on electrochemical performance of Si-based electrode was investigated, and it is found that as the particle size decreases in the studied range, the Si particles show a lower specific capacity and a higher irreversible capacity loss(ICL). Furthermore, an oxide layer with thickness of ~3 nm was detected on the surface of the as-received Si nanoparticles, and this layer can be effectively removed by hydrofluoric acid(HF) etching,resulting in much improved electrochemical performance over the as-received samples. 展开更多
关键词 LITHIUM-ION batteries Anode Silicon nanoparticles Wet GRINDING MILL
Recycling water glass from wet reclamation sewage of waste sodium silicate-bonded sand
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作者 Li-chi Wang Wen-ming Jiang +2 位作者 Xiao-long Gong Fu-chu Liu Zi-tian Fan 《中国铸造:英文版》 SCIE 2019年第3期198-203,共6页
Wet reclamation of waste sodium silicate-bonded sand produces much alkaline sewage and causes pollution. Recycling water glass from wet reclamation sewage of the waste sodium silicate-bonded sand can solve pollution i... Wet reclamation of waste sodium silicate-bonded sand produces much alkaline sewage and causes pollution. Recycling water glass from wet reclamation sewage of the waste sodium silicate-bonded sand can solve pollution issues and generate economic benefits. In this work, the wet reclamation sewage was filtered, and the filtrate was causticized with a quicklime powder to produce a lye. The effects of causticization temperature, causticization time, and the amount of quicklime powder on the causticization rate were studied. The lye was used to dissolve the silica in the filtration residue to prepare a sodium silicate solution. The effects of the mass of filtration residue, dissolution temperature, and dissolution time on sodium silicate modulus were studied. Finally, the recycled water glass was obtained by concentrating the sodium silicate solution, and the bonding strength of the recycled water glass was tested. The results showed that the causticization rate could be improved by increasing the amount of quicklime powder, causticization temperature, and causticization time, and the highest causticization rate was above 92%. Amorphous silica in the filtration residue dissolved in the lye. Increasing the amount of the filtration residue, dissolution temperature, and dissolution time could improve the sodium silicate modulus. The bonding strength of the recycled water glass was close to that of commercial water glass. The recycled water glass could be used as a substitute for the commercial water glass. 展开更多
关键词 WASTE sodium silicate-bonded SAND wet reclamation SEWAGE treatment CAUSTICIZATION RECYCLING water glass
Wet Pressing Models to Reduce Energy Consumption in Papermaking 预览
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作者 J.David McDonald Richard J.Kerekes Joe R.Zhao 《造纸与生物质材料:英文版》 2019年第1期1-6,共6页
Improved wet pressing reduces the need for drying and consequently energy needed in papermaking. Accordingly, it is desirable to optimize wet pressing, but the process is very complex with many interacting variables. ... Improved wet pressing reduces the need for drying and consequently energy needed in papermaking. Accordingly, it is desirable to optimize wet pressing, but the process is very complex with many interacting variables. It is therefore desirable to employ a mathematical model that accounts for the major variables to estimate the effects of changes in equipment and operating variables. This paper descibes such a model called the Decreasing Permeability Model (DPM). Mill and pilot plant applications over a wide range of basis weights for paper and paper board are described. 展开更多
关键词 WET PRESSING DECREASING Permeability MODEL (DPM) PAPERMAKING water removal rewet mathemeitical MODEL
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Wet-spun poly(ionic liquid)-graphene hybrid fibers for high performance all-solid-state flexible supercapacitors 预览
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作者 Karthikeyan Gopalsamy Qiuyan Yang +3 位作者 Shengying Cai Tieqi Huang Zhengguo Gao Chao Gao 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第7期104-110,共7页
It is crucial to develop flexible and wearable electronic devices that have attracted tremendous interest due to their merits on compactness,flexibility and high capacitive properties.Herein we report the continuously... It is crucial to develop flexible and wearable electronic devices that have attracted tremendous interest due to their merits on compactness,flexibility and high capacitive properties.Herein we report the continuously ordered macroscopic poly(ionic liquid)-graphene fibers by wet spinning method via liquid crystal assembly for supercapacitor application.The fabricated all-solid-state supercapacitors exhibited a high areal capacitance(268.2 mF cm 2)and volumetric capacitance(204.6 F cm 3)with an outstanding areal energy density(9.31μWh cm-2)and volumetric energy density(8.28 mWh cm-3).The fiber supercapacitors demonstrated exceptional cycle life for straight electrodes of about 10,000 cycles(94.2%capacitance retention)and flexibility at different angles(0°,45°,90°,180°)along with a good flexible cycling stability after 6000 cycles(92.7%capacitance retention).To date,such a novel poly(ionic liquid)-graphene fiber supercapacitors would be a new platform in real-time flexible electronics. 展开更多
关键词 GRAPHENE fiber Poly(ionic liquid) WET spinning SUPERCAPACITORS Flexibility
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Preparation of Polyimide Fiber/ Thermoplastic Resin Composites with Improved Mechanical Properties 预览
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作者 Hongyang Dang Le Chen +3 位作者 Guoliang Zhang Ruqiang Zhang Jie Chen Zhu Long 《造纸与生物质材料:英文版》 2019年第3期30-38,共9页
As a high-performance material for preparing composite materials, polyimide fibers suffer from many potential drawbacks, including poor bonding with other substrates, which results in composite materials with poor mec... As a high-performance material for preparing composite materials, polyimide fibers suffer from many potential drawbacks, including poor bonding with other substrates, which results in composite materials with poor mechanical properties. Therefore, this study proposed a simple and rapid technique for obtaining loose, porous polyimide fiber papers by implementing a wet method using equal amounts of polyimide fiber and polyimide fiber paper as reinforcements, respectively. The polyimide resin-based composite materials were prepared by hand lay-up and hot pressing. The results showed that the paper-based reinforcement exhibited high porosity and the fibers were arranged with a uniform pore size distribution. The tensile properties, bending performance, and interlaminar shear performance of the paper-based composite improved by 130%, 108%, and 34.5%, respectively, compared to those of the fiberbased counterpart. The factors affecting the mechanical properties of the composites were analyzed based on the fiber length, fiber beating or lack thereof, and the basis weight of the paper. The increased uniformity of the polyimide fiber paper changed the ordering of the fibers and resolved drawbacks such as difficult dispersion, uneven pore size distribution, and poor mechanical properties related to single fibers in the resin-based composite material. 展开更多
关键词 composites POLYIMIDE FIBER POLYIMIDE FIBER paper WET FORMING technology mechanical properties
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某越野军车驾驶室防雨密封性优化 预览
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作者 段国伟 于洪亮 《汽车实用技术》 2019年第4期98-100,共3页
驾驶室漏雨是军车研发制造中需要重点关注和解决的问题,漏雨涉及的原因较多,分析较为复杂,是整车质量控制的重点之一。以某军车为案例,从车门内外板的焊接工艺、装配车门内密封条钣金高度、角窗玻璃框的结构等方面开展漏水的原因分析和... 驾驶室漏雨是军车研发制造中需要重点关注和解决的问题,漏雨涉及的原因较多,分析较为复杂,是整车质量控制的重点之一。以某军车为案例,从车门内外板的焊接工艺、装配车门内密封条钣金高度、角窗玻璃框的结构等方面开展漏水的原因分析和控制措施探讨,介绍了驾驶室漏水的问题来源和整改措施,为后续军车的定型及批量生产打下坚实的基础。 展开更多
关键词 淋雨 焊接 密封条 密封胶
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A Novel Method for Synthesizing p -Benzoquinone by Direct Catalytic Oxidation of Benzene with Hydrogen Peroxide over Copper-Doped TS-1 预览
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作者 Chenxiaodong Li Qingjun Zhang Aiwu Zeng 《天津大学学报:英文版》 EI CAS 2019年第5期517-526,共10页
E xisting methods for synthesizing p -benzoquinone have drawbacks with respect to environmental protection, production scale, or industrial value. Therefore, it is imperative that a simple and environmentally friendly... E xisting methods for synthesizing p -benzoquinone have drawbacks with respect to environmental protection, production scale, or industrial value. Therefore, it is imperative that a simple and environmentally friendly alternative be developed. The approach that involves preparing p -benzoquinone by the catalytic oxidation of benzene with hydrogen peroxide (H 2 O 2 ) over copper-modi ed titanium silicalite-1 (Cu/TS-1) has a certain superiority due to its green synthesis and mild reaction condi- tions. In this study, Cu/TS-1 catalyst was prepared by the wet impregnation of TS-1 with an aqueous solution of Cu(NO 3 ) 2 and then characterized by X-ray di raction, Fourier transform infrared spectroscopy, di use re ectance UV Vis spectros- copy, scanning electron microscopy, inductively coupled plasma mass spectrometry, X-ray uorescence, and analysis of the N 2 adsorption desorption isotherms. The results reveal that Cu species exist mainly in the form of amorphous CuO that is well dispersed on the surface of catalysts, with no major change in the molecular sieve framework. After optimizing the reaction conditions, a desirable p -benzoquinone selectivity (88.4%) and benzene conversion (18.3%) were obtained when the doping of Cu in Cu/TS-1 is 1.95 wt%. In addition, Cu/TS-1 can be conveniently regenerated, showing a slight decrease in catalytic capability after initial use, which then stabilizes in subsequent circulations. The satisfactory stability and low cost of synthesizing Cu/TS-1 give this method considerable potential for further industrialization. 展开更多
关键词 Catalytic oxidation BENZENE P -Benzoquinone Copper Titanium SILICALITE-1 (TS-1) Wet impregnation
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Synthesis and AO Resistant Properties of Novel Polyimide Fibers Containing Phenylphosphine Oxide Groups in Main Chain
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作者 Yong Zhao Hong Gao +4 位作者 Guo-Min Li Fang-Fang Liu Xue-Min Dai Zhi-Xin Dong Xue-Peng Qiu 《高分子科学:英文版》 SCIE CAS CSCD 2019年第1期59-67,共9页
A series of co-polyimide(PI)fibers containing phenylphosphine oxide(PPO)group were synthesized by incorporating the bis(4-aminophenoxy)phenyl phosphine oxide(DAPOPPO)monomer into the PI molecular chain followed by dry... A series of co-polyimide(PI)fibers containing phenylphosphine oxide(PPO)group were synthesized by incorporating the bis(4-aminophenoxy)phenyl phosphine oxide(DAPOPPO)monomer into the PI molecular chain followed by dry-jet wet spinning.The effects of DAPOPPO molar content o n the atomic oxygen(AO)resistance of the fibers were investigated systematically.When the AO fluence increased from 0 atoms cm^-2 to 3.2×l0^20 atoms.cm^-2,the mass loss of the fibers showed the dependence on DAPOPPO molar content in co-PI fibers.The PI fiber containing 40%DAPOPPO showed lower mass loss compared to those containing 0%and 20%DAPOPPO.At higher AO fluence,the higher DAPOPPO content gave rise to dense carpet-like surface of fibers.XPS results indicated that the passivated phosphate layer was deposited on the fiber surface when exposed to AO,which effectively prevented fiber from AO erosion.With the DAPOPPO content increasing from 0%to 40%,the retentions of tensile strength and initial modul us for the fibers exhibited obvious growth from 44%to 68%,and 59%to 70%,after A O exposure with the fluence of 3.2×l0^20 atoms cm^-2.T h e excellent AO resistance benefits the fibers for application in low Earth orbit as flexible construction components. 展开更多
关键词 POLYIMIDE fibers Bis(4-aminophenoxy)phenyl PHOSPHINE oxide(DAPOPPO) Dry-jet wet SPINNING AO resistance
Catalytic wet oxidation of N,N-dimethyl formamide over ruthenium supported on CeO2 and Ce0.7Zr0.3O2 catalysts
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作者 Jiawen Gong Dongzhi Li +4 位作者 Li Wang Wangcheng Zhan Yanglong Guo Yunsong Wang Yun Guo 《中国稀土学报:英文版》 SCIE EI CAS CSCD 2019年第3期265-272,共8页
A series of Ru supported on CeO2 and Ce0.7Zr0.3O2(CeZrO) was prepared by incipient-wet impregnation method and investigated in the catalytic wet oxidation of N,N-dimethyl formamide(DMF) in batch reactor. The physicoch... A series of Ru supported on CeO2 and Ce0.7Zr0.3O2(CeZrO) was prepared by incipient-wet impregnation method and investigated in the catalytic wet oxidation of N,N-dimethyl formamide(DMF) in batch reactor. The physicochemical property of the catalysts was characterized by Brunauer-Emmett-Teller(BET), X-ray diffraction(XRD), H2 temperature-programmed reduction(H2-TPR), X-ray photoelectron spectroscopy(XPS) and thermogravimetry(TG). Compared with 3%Ru/CeO2, 3%Ru/Ce0.7Zr0.3O2 catalyst exhibits much higher performance for DMF degradation due to the promotion of Ru dispersion and the transfer of active oxygen, and 99% DMF conversion and 97% COD elimination are obtained at 453 K,2.5 MPa oxygen pressure after 5 h. The reaction mechanism of DMF degradation was suggested. The carbonaceous species deposition and oxidation of Ru can be responsible for catalyst deactivation. And the catalyst activity can be recovered by air calcination and H2 reduction. 展开更多
关键词 Catalytic wet oxidation N N-dimethyl FORMAMIDE Ru Degradation Catalyst DEACTIVATION and regeneration Rare earths
Determination of Inorganic Elements in Paris daliensis H.Li et V.G.Souku and Paris dulongensis H.Li et S.Kuritap by ICP-OES 预览
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作者 Jixiu SHEN Zhongjie HUANG +3 位作者 Risha WEIZE Xuexue LI Yunzhang XU Yuan LIU 《药用植物研究(英文版)》 2019年第1期37-39,共3页
[Objectives] To determine 29 kinds of inorganic elements in samples of Paris daliensis H.Li et V.G.Souku and P. dulongensis H.Li et S.Kuritap produced in different regions, and to measure the content of 10 key inorgan... [Objectives] To determine 29 kinds of inorganic elements in samples of Paris daliensis H.Li et V.G.Souku and P. dulongensis H.Li et S.Kuritap produced in different regions, and to measure the content of 10 key inorganic elements: chromium(Cr), manganese(Mn), iron(Fe), copper(Cu), mercury(Hg), zinc(Zn), arsenic(As), antimony(Sr), cadmium(Cd) and lead(Pb). [Methods] The wet digestion and technique of inductively coupled plasma optical emission spectrometry(ICP-OES) were employed. [Results] Under the experimental conditions, elements were not related to each other, and many kinds of elements could be measured at the same time;toxic and heavy metals in samples of P. daliensis H.Li et V.G.Souku and P. dulongensis H.Li et S.Kuritap did not exceed the limit;Hg was not detected in all samples. [Conclusions] This method is simple, easy to operate and reproducible. It can be used for the detection of inorganic elements in P. daliensis H.Li et V.G.Souku and P. dulongensis H.Li et S.Kuritap;the heavy metals and Hg of the rhizome meet the requirements of the limit of medicinal materials. 展开更多
关键词 PARIS daliensis H.Li ET V.G.Souku P.dulongensis H.Li ET S.Kuritap Inorganic element Wet DIGESTION Inductively coupled plasma optical emission spectrometry(ICP-OES) Heavy metals
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Effects of mechanical activation on the digestion of ilmenite in dilute H2SO4
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作者 Xiaomei Wang Chun Li +4 位作者 Hairong Yue Shaojun Yuan Changjun Liu Siyang Tang Bin Liang 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第3期575-586,共12页
The commercial sulfate process for pigment production uses concentrated sulfuric acid(>85 wt%H2SO4)as feeding material and discharges 8–10 tons of spend dilute acid(20 wt%H2SO4)per ton of product.Re-using spend ac... The commercial sulfate process for pigment production uses concentrated sulfuric acid(>85 wt%H2SO4)as feeding material and discharges 8–10 tons of spend dilute acid(20 wt%H2SO4)per ton of product.Re-using spend acid to leach ilmenite can cut the waste emission and save fresh feeding acid.However,the leaching reaction with dilute acid is very slow and the digestion efficiency is fairly low.This paper describes a wet-milling process to enhance the dilute-acid leaching of ilmenite that makes it possible to produce TiO2 pigment in a more environmentally benign routine.The leaching kinetic study of unmilled ilmenite,dry milled 60 min ilmenite and wet milled 60 min ilmenite was conducted by revision of the shrinking core model(SCM),incorporation of particle size distribution(PSD)into SCM.The results revealed that mechano-chemical activation method significantly increased the leaching efficiency of titanium from 36%to 76%by reducing the particle size and increasing the reaction contact area.On the other hand,the milling process increased the lattice deformation and amorphization of crystalline,which lowered the activation energies in the leaching process.Compared with dry milling operation,wet milling is more effective,the particle size distribution of wet-milled ilmenite was much narrower,smaller,and more uniform.Wet milling of ilmenite makes the leaching reaction with dilute acid(60 wt%H2SO4)practicable and the re-use of spend acid becomes possible and economical. 展开更多
关键词 ILMENITE Mechanical activation Sulfuric-acid LEACHING Wet MILLING Kinetics
几种锰矿的冶炼及提纯技术分析 预览
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作者 杨俊卿 黎明 喻朝海 《现代矿业》 CAS 2019年第12期141-143,172共4页
为合理高效的开发利用锰矿资源,对硅酸盐及氧化物类型锰矿的几种冶炼方法进行了评述分析,综述了不同地区和种类的锰产品的提纯和生产工艺过程,总结了相关因素对锰矿的纯度及生产过程的影响。通过分析得出重选是锰矿冶炼中相对经济、绿... 为合理高效的开发利用锰矿资源,对硅酸盐及氧化物类型锰矿的几种冶炼方法进行了评述分析,综述了不同地区和种类的锰产品的提纯和生产工艺过程,总结了相关因素对锰矿的纯度及生产过程的影响。通过分析得出重选是锰矿冶炼中相对经济、绿色和高效的手段,而磁选和湿法冶炼可进一步在精矿获取中发挥重要作用,为锰矿的开采和利用提供了理论支撑。 展开更多
关键词 重选 磁选 湿法 冶炼
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Mathematical Model of Drag Torque with Surface Tension in Single-Plate Wet Clutch 预览
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作者 Zengxiong Peng Shihua Yuan 《中国机械工程学报:英文版》 SCIE EI CAS CSCD 2019年第2期93-99,共7页
Reduction of drag torque in disengaged wet clutches is essential for transmission research because it is one of the potentials of e ciency improvement. Aeration of oil film between two closely rotating plates promotes... Reduction of drag torque in disengaged wet clutches is essential for transmission research because it is one of the potentials of e ciency improvement. Aeration of oil film between two closely rotating plates promotes the decrease of drag torque at high speed region. The e ects of surface tension and static contact angles during aeration are nonnegligible showed by test results. The traditional lubrication model does not adequately predict the experimental results with di erent surface tension and contact angles during aeration. Hence, in this present paper, contact angles between Aluminum and Teflon materials were firstly measured, and the drag torques under two di erent contact angles were examined experimentally. An improved lubrication model of drag torque based on Navier–Stokes equations at the gas-liquid interface was built. The lubrication boundary condition was modified to introduce the e ects of surface tension and contact angle. The model shows that the e ects at the beginning of aeration of oil film are significant. These e ects almost occur at stationary plate due to low Reynolds number and Weber number. The model shows that an increase in the surface tension promotes aeration, but does not a ect the peak drag torque. Increasing contact angle also promotes the aeration, and accelerates the decrease of drag torque. The larger contact angle is, the smaller the peak drag torque will be. A computational fluid dynamics(CFD) model based on volume of fluid(VOF) method was presented to validate the interface shape when aeration occurs. The model prediction has a good agreement with experimental observations for Aluminum plates and Teflon plates. The modified lubrication model of drag torque gives a convenient description of the e ects of surface tension and contact angel, and lays down a frame to understand the beginning of aeration. 展开更多
关键词 Drag TORQUE WET CLUTCH Surface tension Contact ANGLE
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Structural control of silica aerogel fibers for methylene blue removal
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作者 MENG Si ZHANG JunYan +4 位作者 XU Wen CHEN WenPing ZHU LiPing ZHOU Zhe ZHU MeiFang 《中国科学:技术科学英文版》 SCIE EI CAS CSCD 2019年第6期958-964,共7页
The development of efficient adsorbents is significant for the miniaturization and cost reduction of water purifying facility. In our previous study, a new kind of silica aerogel fibers(SAFs) with hierarchical structu... The development of efficient adsorbents is significant for the miniaturization and cost reduction of water purifying facility. In our previous study, a new kind of silica aerogel fibers(SAFs) with hierarchical structure and hollow structure were developed, which shows outstanding mass transport property and adsorption performance. Herein, we further control and study the hierarchical structure and hollow structure of silica aerogel fibers by changing the sulfuric acid concentration of ageing bath and spinning speed. For removing methylene blue, A0 W120 SAFs sample, with DI water as ageing bath and a winding speed of 120 mm/s,presents the best mass transport property and adsorption performance, as they possess larger pore sizes in the outer layer, thinner fiber wall and higher degree of hollowness. The removal rates of methylene blue by A0 W120 SAFs sample is up to 91.6% and 98.2% in 2 and 5 min, respectively, which are at least 30% higher than other comparable commercial adsorbents, while the adsorption capacity of methylene blue reaches up to 139.1 mg/g. 展开更多
关键词 AEROGEL fibers HIERARCHICAL HOLLOW WET SPINNING adsorption
One-step synthesis of TiO2 nanoparticles using simple chemical technique 预览
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作者 Majid Farahmandjou 《材料工程研究(英文)》 2019年第1期15-19,共5页
Titanium dioxide nanoparticles (TiO2) have been extensively investigated because of its high chemical sustainability, optic properties, and adaptation to the environment. These studies include applications in heteroge... Titanium dioxide nanoparticles (TiO2) have been extensively investigated because of its high chemical sustainability, optic properties, and adaptation to the environment. These studies include applications in heterogeneous catalysts, solar cells, coating technology, and electrical devices. TiO2 particles in the nanometer scale can remove limitations, such as the absorbance of organic materials, because of a high surface area to volume ratio. Titanium dioxide nanoparticles, were synthesized using a simple wet chemical method. Their physico-chemical properties were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The TEM results showed that the mean size of assynthesized TiO2 was 5 nm with high crystalline anatase phase. The SEM observations revealed that the size of nanoparticles increased with annealing temperature and the morphology of the particles changed to the spherical shape. The crystal structure of the nanoparticles before and after annealing was done by XRD analysis. The rutile phase was formed after heat treatment at 600oC for 3 hours. 展开更多
关键词 TiO2 NANOPARTICLES WET CHEMICAL synthesis RUTILE phase
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