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Determination of bemegride and its Salts in Cosmetics by HPLC and Their Verification by HPLC-MS/MS 预览
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作者 Guo Xiangyu Meng Xianshuang +4 位作者 Bai Hua Ma Qiang Lv Yueguang Chen Meng Wang Chun 《日用化学品科学(英文版)》 2019年第1期68-72,共5页
A high-performance liquid chromatography (HPLC) method has been developed for the determination of bemegride and its salts in cosmetics. A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) m... A high-performance liquid chromatography (HPLC) method has been developed for the determination of bemegride and its salts in cosmetics. A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was used for the verification of the analytical results. Cosmetic samples were ultrasonically extracted with methanol, centrifuged and filtered by microporous membrane filter prior to instrumental analysis. The chromatographic separation of the analytes was performed using a Symmetry C18 (4.6 mm × 250 mm, 5 μm) column. The quantitation was carried out by external standard method. The experimental results indicated that the limit of quantitation (LOQ) for bemegride and its salts was 0.5 mg/kg. The mean recoveries at three spiked levels ranged from 85.1% to 107.4% with the relative standard deviations (RSDs) between 3.7% and 9.3%. The suspected positive samples were subjected to further verification by HPLC-MS/ MS. The method is accurate, rapid, sensitive and can be used for the inspection of cosmetics. 展开更多
关键词 COSMETICS bemegride HIGH-PERFORMANCE LIQUID chromatography HIGH-PERFORMANCE LIQUID chromatographytandem mass SPECTROMETRY
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In teg rati ng organizati on al lear ning with high-performance work system and entrepreneurial orientation: a moderated mediation framework
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作者 Chunling Zhu Anqi Liu Yangwen Wang 《中国工商管理研究前沿:英文版》 2019年第2期169-192,共24页
This study proposes a moderated mediation model to investigate the relationship between organizational learning and firm performance. We argue that entrepreneurial orientation mediates the positive effect of organizat... This study proposes a moderated mediation model to investigate the relationship between organizational learning and firm performance. We argue that entrepreneurial orientation mediates the positive effect of organizational learning on firm performance. Furthermore, the relationship between organizational learning and entrepreneurial orientation is strengthened when firms employ a higher level of high-performance work system. Hypotheses are supported by data from 181 firms operating in the manufacturing and service industries in China. Statistical results further reveal that a high-performance work system has different moderating effects on exploitative learning and exploratory learning. This research extends our understanding of organizational learning theory, entrepreneurship and human resource management literature by cross-fertilizing constructs in these fields with empirical evidence. 展开更多
关键词 ORGANIZATIONAL LEARNING ORGANIZATIONAL performance ENTREPRENEURIAL orientation HIGH-PERFORMANCE work system (HPWS) Exploitative LEARNING EXPLORATORY LEARNING
High-Performance and Multifunctional Cement-Based Composite Material 预览
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作者 Victor C. Li 《工程(英文)》 2019年第2期250-260,共11页
Concrete is a continuously evolving material, and even the definition of high-performance concrete has changed over time. In this paper, high-performance characteristics of concrete material are considered to be those... Concrete is a continuously evolving material, and even the definition of high-performance concrete has changed over time. In this paper, high-performance characteristics of concrete material are considered to be those that support the desirable durability, resilience, and sustainability of civil infrastructure that directly impact our quality of life. It is proposed that high-performance material characteristics include tensile ductility, autogenous crack-width control, and material “greenness.” Furthermore, smart functionalities should be aimed at enhancing infrastructure durability, resilience, and sustainability by responding to changes in the surrounding environment of the structure in order to perform desirable functions, thus causing the material to behave in a manner more akin to certain biological materials. Based on recent advances in engineered cementitious composites (ECCs), this paper suggests that concrete embodying such high-performance characteristics and smart multifunctionalities can be designed, and holds the potential to fulfill the expected civil infrastructure needs of the 21st century. Highlights of relevant properties of ECCs are provided, and directions for necessary future research are indicated. 展开更多
关键词 HIGH-PERFORMANCE concrete MULTIFUNCTION Smart CEMENT-BASED composite Durability RESILIENCE Sustainability Infrastructure
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生物基环氧树脂高性能化和功能化的研究进展 预览
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作者 翁志焕 李佳惠 +3 位作者 戚裕 王锦艳 张守海 蹇锡高 《中国材料进展》 CAS CSCD 北大核心 2019年第10期999-1008,共10页
环氧树脂是三大热固性高分子材料之一,具有优异的综合性能,在涂料、粘合剂、电子电器等许多领域得到了广泛的应用。采用可再生生物质原料制备生物基环氧树脂,能够缓解化石能源危机和减轻环境污染,符合社会可持续发展的需求。主要结合作... 环氧树脂是三大热固性高分子材料之一,具有优异的综合性能,在涂料、粘合剂、电子电器等许多领域得到了广泛的应用。采用可再生生物质原料制备生物基环氧树脂,能够缓解化石能源危机和减轻环境污染,符合社会可持续发展的需求。主要结合作者课题组和国内外其他研究团队的研究,总结了近年来生物基环氧树脂在高性能化和功能化方面的研究进展,尤其围绕制约生物基环氧树脂应用的主要问题,如耐热性不高、阻燃性和韧性差,希望为未来生物基环氧树脂的发展方向提供借鉴。 展开更多
关键词 生物基 环氧树脂 高性能 功能化
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Metal-organic frameworks derived flower-like Co3O4/nitrogen doped graphite carbon hybrid for high-performance sodium-ion batteries
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作者 Haifeng Xu Guang Zhu Baoming Hao 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第1期100-108,共9页
In this work, a novel flower-like cobalt-based metal organic frameworks(MOFs) self-assembled by Co2+ and nicotinic acid have been designed and synthesized. After a simple annealing treatment, Co3O4 nanoparticles in-si... In this work, a novel flower-like cobalt-based metal organic frameworks(MOFs) self-assembled by Co2+ and nicotinic acid have been designed and synthesized. After a simple annealing treatment, Co3O4 nanoparticles in-situ decorating on nitrogen doped graphite carbon-sheet(Co3O4/NC) were obtained. The resultant Co3O4/NC hybrid with unique flower-like structure and ration combination of Co3O4 nanoparticles and nitrogen doped graphite carbon, endowing the hybrid with enhanced electrical conductivity,short ion diffusion pathways and rich porosity to the materials, which can largely alleviate the problems of Co3O4 such as inferior intrinsic electrical conductivity, sluggish ion kinetics and large volume change upon cycling. When evaluated as anode material for sodium-ion batteries(SIBs), the Co3O4/NC hybrid exhibits satisfied reversible capacity(213.9 mAh g^-1 after 100 cycles at 0.1 A g^-1 ), excellent rate capability(145.4 m Ah g^-1 at 2 A g^-1 and 130.1 mAh g^-1 at 4 A g^-1 ) and robust long-term cycling stability(120.1 m Ah g^-1 after 2000 cycles at 0.5 A g^-1 ), showing great potential for high-performance SIBs. 展开更多
关键词 Co3O4/NC HYBRID METAL-ORGANIC frameworks Sodium-ion batteries HIGH-PERFORMANCE
Technological development and engineering applications of novel steel-concrete composite structures
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作者 Jianguo NIE Jiaji WANG +2 位作者 Shuangke GOU Yaoyu ZHU Jiansheng FAN 《结构与土木工程前沿:英文版》 EI CSCD 2019年第1期1-14,共14页
In view of China's development trend of green building and building industrialization,based on the emerging requirements of the structural engineering community,the development and proposition of novel resourcesav... In view of China's development trend of green building and building industrialization,based on the emerging requirements of the structural engineering community,the development and proposition of novel resourcesaving high-performance steel-concrete composite structural systems with adequate safety and durability has become a kernel development trend in structural engineering.This paper provides a state of the art review of China's cutting-edge research and technologies in steel-concrete composite structures in recent years,including the building engineering,the bridge engineering and the special engineering.This paper summarizes the technical principles and applications of the long-span bi-directional composite structures,the long-span composite transfer structures,the comprehensive crack control technique based on uplift-restricted and slip-permitted (URSP)connectors,the steel plate concrete composite (SPCC)strengthen technique,and the innovative composite joints.By improving and revising traditional structure types, the comprehensive superiority of steel-concrete composite structures is well elicited.The research results also indicate that the high-performance steel-concrete composite structures have a promising popularizing prospect in the future. 展开更多
关键词 HIGH-PERFORMANCE COMPOSITE structure bi-directional COMPOSITE COMPOSITE transfer uplift-restricted and slip- permitted connectors steel plate concrete COMPOSITE STRENGTHEN
High-performance self-assembly MnCo2O4 nanosheets for asymmetric supercapacitors 预览
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作者 Jianwei Li Dongbin Xiong +2 位作者 Linzhe Wang Maleki Kheimeh Sari Hirbod Xifei Li 《能源化学:英文版》 CSCD 2019年第10期66-72,共7页
In this study,MnCo2O4 nanosheets were proposed to be utilized as an electrode material for supercapacitors.A two-step hydrothermal method with post-annealing treatment was employed in preparation of the nanostructures... In this study,MnCo2O4 nanosheets were proposed to be utilized as an electrode material for supercapacitors.A two-step hydrothermal method with post-annealing treatment was employed in preparation of the nanostructures.MnCo2O4 electrode delivered a high specific capacitance of 2000 F g^-1 at 0.5 A g^-1,remarkable high-rate capability of 1150 F g^-1 at 20 A g^-1,and an excellent cycling stability of 92.3%at 5 A g^-1 after 5000 cycles.It is found that a three-electrode supercapacitor based on MnCo2O4 exhibits a promising electrochemical performance,better than the other similar materials,benefited from the synergistic effects of MnCo2O4 nanosheets.In fact,the self-assembly of nanosheets structure with high specific surface area and mesoporous structure can potentially enhance the electrochemical performance of supercapacitors. 展开更多
关键词 HIGH-PERFORMANCE SELF-ASSEMBLY MnCo2O4 NANOSHEETS ASYMMETRIC SUPERCAPACITORS
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Production and stability study of a hospital parenteral nutrition solution for neonates 预览
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作者 Anne-Laure Yailian Céline Serre +6 位作者 Justine Fayard Marina Faucon Patrick Thomaré Christine Pivot Florence Vételé Fabrice Pirot Emmanuelle Olivier 《药物分析学报:英文版》 CAS CSCD 2019年第2期83-90,共8页
Standard parenteral nutrition solutions are mixtures comprising interacting components that may degrade themselves over time.The objective of this study was to investigate the physicochemical and microbiological stabi... Standard parenteral nutrition solutions are mixtures comprising interacting components that may degrade themselves over time.The objective of this study was to investigate the physicochemical and microbiological stability of a hospital preparation for parenteral nutrition in neonatology.The analyses were performed throughout the storage of the preparations at 2–8℃(up to 4 months).The extent of stability was based on the determination of amino acids dosage,visual and physicochemical properties (glucose and electrolytes concentrations,pH and osmolality measurements,particle counting) and microbiological analysis (sterility test).A thermal degradation of ascorbic acid was conducted to evaluate the antioxidant properties of the parenteral mixture.Physicochemical and microbiological controls were found to comply with the specifications.Amino acids showed a good stability throughout the 4months storage except for cysteine,which was progressively degraded to cystine,conferring a yellow coloration to parenteral solutions.Parenteral nutrition standards solutions remain stable for 4 months at 2–8℃,ensuring safe administration in preterm infants. 展开更多
关键词 STABILITY-INDICATING method study PARENTERAL NUTRITION NEONATOLOGY Amino acids High-performance liquid CHROMATOGRAPHIC
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金属高性能增材制造技术在航空领域中的研究 预览
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作者 张艳 《工业加热》 CAS 2019年第3期78-80,84共4页
金属高性能增材制造技术在航空领域备受青睐,实现了稳定发展,主要是由于其能够在缺乏模具与锻造的前提下,为航空企业制造各种复杂零件,一体化成型承力结构件,降低零部件重量,节省生产时间,还能够减少所需零件数量,大大节约成本,保证可... 金属高性能增材制造技术在航空领域备受青睐,实现了稳定发展,主要是由于其能够在缺乏模具与锻造的前提下,为航空企业制造各种复杂零件,一体化成型承力结构件,降低零部件重量,节省生产时间,还能够减少所需零件数量,大大节约成本,保证可靠性与稳定性。其中金属高性能增材制造技术主要包括两种技术方向,即同步送粉高能束熔覆技术与粉末床成型技术,能够保障成型结构件具备良好力学性能,与锻件几乎相当,这就直接为提高飞机与航空发动机机构设计水平与质量,实现优化设计奠定了坚实的基础。据此,本文主要对在航空领域中的金属高性能增材制造技术进行深入探究。 展开更多
关键词 航空领域 金属 高性能 增材 制造技术
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高性能网络协议栈兼容性研究 预览
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作者 姜惠友 李峻峰 李丹 《电信科学》 2019年第5期25-31,共7页
人工智能系统的海量数据处理需要很高的网络吞吐来支撑,网络协议栈作为上层人工智能应用和底层高速硬件网卡之间的桥梁,对整个系统的网络性能起到关键性作用。通过对主流网络协议栈兼容性进行详细对比分析,发现目前各类协议栈兼容性普... 人工智能系统的海量数据处理需要很高的网络吞吐来支撑,网络协议栈作为上层人工智能应用和底层高速硬件网卡之间的桥梁,对整个系统的网络性能起到关键性作用。通过对主流网络协议栈兼容性进行详细对比分析,发现目前各类协议栈兼容性普遍较低,导致人工智能应用移植困难等问题。提出了高性能用户态网络协议栈的高兼容性设计构想,使各类传统应用无需修改源码即可获得网络性能的提升,讨论了高性能协议栈的后续发展方向。 展开更多
关键词 兼容性 网络协议栈 高性能
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Purines Change at Acupoints along the Pericardium Meridian in Healthy and Myocardial Ischemic Rats
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作者 ZHOU Yu-mei ZHUANG Yi +5 位作者 CAI Ding-jun LV Pei-ran ZHOU Jie WAN Min REN Yu-lan LIANG Fan-rong 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2019年第4期285-291,共7页
Objective: To quantify the purine concentrations of the acupoints along the pericardium and nonpericardium meridians under healthy and myocardial ischemia conditions to investigate the relationship between acupoint pu... Objective: To quantify the purine concentrations of the acupoints along the pericardium and nonpericardium meridians under healthy and myocardial ischemia conditions to investigate the relationship between acupoint purine change and body functional status in rats.Methods: A total of 70 rats underwent an operation for myocardial ischemia,while 40 of them survived.They were randomly assigned to the following 5 subgroups:Neiguan(PC 6),Quze(PC 3),Tianquan(PC 2),Quchi(LI 11),and Jianyu(LI 15).Simultaneously,another40 healthy rats were also randomized into the same 5 subgroups as the control group.The tissue ?uids at the acupoints were collected by microdialysis for 30 min.Subsequently,the concentration of adenosine triphosphate(ATP),adenosine diphosphate(ADP),adenosine monophosphate(AMP),and adenosine(ADO) were quanti?ed using the high-performance liquid chromatography method.Results: Compared with the healthy group,the ADO at PC 6(P=0.012),PC 3(P=0.038),PC 2(P=0.024),and LI 15(P=0.042) obviously increased in the model group,while no signi?cant difference was observed at LI 11(P=0.201).However,ATP,ADP,and AMP manifested no significant changes in these areas,except for ATP at LI 15(P=0.036).Conclusions: Myocardial ischemia could induce an increase in ADO at acupoints of the upper arm and shoulder area,suggesting that the body functional status could affect the responsiveness of acupoints.The status of these acupoints could be pathogenically activated by disease,and distribution following some speci?c courses. 展开更多
关键词 acupoint MYOCARDIAL ischemia PERICARDIUM meridian PURINE adenosine MICRODIALYSIS high-performance liquid chromatography
Chenopodium ambrosioides induces an endothelium-dependent relaxation of rat isolated aorta
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作者 Asmae Assaidi Ikram Dib +9 位作者 Monique Tits Luc Angenot Said Bellahcen Nourelhouda Bouanani Abdelkhaleq Legssyer Mohammed Aziz Hassane Mekhfi Mohammed Bnouham Michel Frederich Abderrahim Ziyyat 《结合医学学报:英文版》 CAS CSCD 2019年第2期115-124,共10页
Objective: This study aims to evaluate the vasodilatory effect of Chenopodium ambrosioides on the isolated rat aorta, and to explore its mechanism of action. Methods: The vasorelaxant effect and the mode of action of ... Objective: This study aims to evaluate the vasodilatory effect of Chenopodium ambrosioides on the isolated rat aorta, and to explore its mechanism of action. Methods: The vasorelaxant effect and the mode of action of various extracts from the leaves of C. ambrosioides were evaluated on thoracic aortic rings isolated from Wistar rats. In addition, ethyl acetate and methanol fractions were analyzed, using thin-layer chromatography and high-performance liquid chromatography techniques, for their polyphenolic con tent. Results: The various active extracts of C. ambrosioides at four concentrations (10 3, 10 2, 10 1* and 1 mg/mL) relaxed the con traction elicited by phe ny lephri ne, in a concentration-depende nt manner. This effect seems to be endothelium-dependent, since the vasodilatory effect was entirely absent in denuded aortic rings. The vasorelaxant effect of the methanol fraction (MF) of C. ambrosioides at 1 mg/mL was also inhibited by atropine and tetraethylammonium. This effect remained unchanged by Nw-nitro-L-arginine methyl ester hydrochloride and glibenclamide. The preliminary phytochemical analysis showed that the leaves of C. ambrosioides are rich in phenolic and flavonoid derivatives. Conclusion: These results suggest that the MF of C. ambrosioides produces an endothelium-dependent relaxation of the isolated rat aorta, which is thought to be mediated mainly through stimulation of the muscarinic receptors, and probably involving the opening of Ca^2+-activated potassium channels. 展开更多
关键词 CHENOPODIUM ambrosioides CHENOPODIACEAE VASORELAXATION Ca^2+-activated potassium channels THIN-LAYER CHROMATOGRAPHY High-performance liquid CHROMATOGRAPHY Plant Complementary and alternative medicine
Analysis of the binding sites with NL-101 to amino acids and peptides by HPLC/MS/MS
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作者 Lingzi Dai Nian Guo +3 位作者 Yaqin Liu Shanshan Shen Qiufu Ge Yuanjiang Pan 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第1期103-106,共4页
The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS... The binding between NL-101, a novel nitrogen mustard anti-cancer drug, with amino acids and peptides has been investigated by high performance liquid chromatography electrospray tandem mass spectrometry(HPLC/ESI-MS/MS). This study offers supporting data of the interaction among drug and amino acids and peptides, which could potentially explain the cytotoxic and mutagenic effects of the drug. Collision-induced dissociation(CID) experiment demonstrated that under the same collision energy, the amino group combined with NL-101 adducts are sensitive and often produce more fragment ions;the carboxyl group combined with NL-101 adducts are hard to break and display fewer fragment ions. In addition, when other group(like sulfhydryl group) of amino acids binds to NL-101, CID spectra show different fragmentation pattern. These differences could display structural information about the drug adducts and be utilized as location of the authentic binding sites. 展开更多
关键词 HIGH-PERFORMANCE liquid chromatography/ TANDEM mass spectrometry NL-101 Amino ACIDS PEPTIDES Binding SITES
Fast, green microwave-assisted synthesis of single crystalline Sb2Se3 nanowires towards promising lithium storage 预览
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作者 Wen Luo Jean-Jacques Gaumet +5 位作者 Pierre Magri Sébastien Diliberto Feng Li Pascal Franchetti Jaafar Ghanbaja Liqiang Mai 《能源化学:英文版》 SCIE EI CAS CSCD 2019年第3期27-33,共7页
In this work, a fast (0.5 h), green microwave-assisted synthesis of single crystalline Sb2Se3 nanowires was developed. For the first time we demonstrated a facile solvent-mediated process, whereby intrigu-ing nanostru... In this work, a fast (0.5 h), green microwave-assisted synthesis of single crystalline Sb2Se3 nanowires was developed. For the first time we demonstrated a facile solvent-mediated process, whereby intrigu-ing nanostructures including antimony selenide (Sb2Se3) nanowires and selenium (Se) microrods can be achieved by merely varying the volume ratio of ethylene glycol (EG) and H2O free from expensive chem-ical and additional surfactant. The achieved uniform Sb2Se3 nanowire is single crystalline along [001] growth direction with a diameter of 100 nm and a length up to tens of micrometers. When evaluated as an anode of lithium-ion battery, Sb2Se3 nanowire can deliver a high reversible capacity of 650.2 mAh g^-1 at 100 mA g^-1 and a capacity retention of 63.8% after long-term 1000 cycles at 1000 mA g^-1, as well as superior rate capability (389.5 mAh g^-1 at 2000 mA g^-1). This easy solvent-mediated microwave syn-thesis approach exhibits its great universe and importance towards the fabrication of high-performance metal chalcogenide electrode materials for future low-cost, large-scale energy storage systems. 展开更多
关键词 Microwave synthesis Sb2Se3 NANOWIRES Solvent-mediated process LITHIUM-ION battery HIGH-PERFORMANCE ANODE
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中小型网站服务器架构设计 预览
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作者 梁剑 石岩岭 《山西大同大学学报:自然科学版》 2019年第3期42-43,75共3页
传统的网站中,为了提高性能使用更多CPU、更大内存、更强的磁盘阵列的小型机,这无疑会使网站初期就要投入大量成本。由于成本的原因,中小型网站不可能选择昂贵的小型机。介绍一个中小型网站的架构设计,使用多台普通服务器搭建网站能够... 传统的网站中,为了提高性能使用更多CPU、更大内存、更强的磁盘阵列的小型机,这无疑会使网站初期就要投入大量成本。由于成本的原因,中小型网站不可能选择昂贵的小型机。介绍一个中小型网站的架构设计,使用多台普通服务器搭建网站能够实现高可靠性、高性能、可伸缩性等特征。 展开更多
关键词 服务器 高性能 可伸缩性
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Integration of Tropical Renewable Energies 预览
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作者 Daltro Garcia Pinatti Rosa Ana Conte +2 位作者 Thiago Hirosse Silva Luis Miguel Paulo Rodolpho de Oliveira Moreira 《能源与动力工程:英文版》 2019年第3期91-96,共6页
Main sources of renewable energy in the tropics are solar thermal and biomass.High-performance concrete(HPC)allows prefabrication of stakes,planks,boards,U-,L-,and I-profiles,prestressed thick-wall cylinders,and arc s... Main sources of renewable energy in the tropics are solar thermal and biomass.High-performance concrete(HPC)allows prefabrication of stakes,planks,boards,U-,L-,and I-profiles,prestressed thick-wall cylinders,and arc sectors.They are used to construct fences,level curves,buildings,contention walls,water and anaerobic tanks,and silos.Biomass production is increased by retention of rain water in the soil by level curves,in riparian tanks,and with fertigation.HPC anaerobic digesters produce biogas,biochar,and liquid fertilizer.Biogas is partially washed in medium-pressure vessel to obtain vehicular methane gas,which is partially burned in engine generator sets,whose combustion gases are fed into a boiler of a thermoelectric unit.The cycle is thermal solar regenerative Rankine cycle with heat recovery.Boiler receives hot water from thermal solar parabolic collectors,burns residual biomass and biochar generating steam for a turbogenerator set and combustion gas for condenser dryer silo,whose exhaustion heat goes to anaerobic digesters. 展开更多
关键词 HIGH-PERFORMANCE concrete profiles thermal solar-biomass energy generation biomass ANAEROBIC DIGESTER BIOGAS
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碳纤维增强高性能热塑性复合材料界面改性的研究进展 预览
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作者 邢开 徐海兵 +3 位作者 颜春 陈刚 陈明达 祝颖丹 《玻璃钢/复合材料》 CAS 北大核心 2019年第5期110-115,共6页
碳纤维增强高性能热塑性复合材料因其卓越的机械性能、易加工、可回收再利用等优势在航空航天、国防军工、轨道交通等尖端领域应用广泛。界面是碳纤维增强高性能热塑性复合材料的薄弱环节,是影响其性能的关键因素之一。复合材料界面改... 碳纤维增强高性能热塑性复合材料因其卓越的机械性能、易加工、可回收再利用等优势在航空航天、国防军工、轨道交通等尖端领域应用广泛。界面是碳纤维增强高性能热塑性复合材料的薄弱环节,是影响其性能的关键因素之一。复合材料界面改性研究一直备受重视。本文总结了碳纤维增强高性能热塑性复合材料界面性能的影响因素,并重点介绍了碳纤维增强高性能热塑性复合材料界面改性的原理和方法。 展开更多
关键词 碳纤维 高性能 热塑性复合材料 界面改性
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Antioxidant compounds and capacities of Gac (Momordica cochinchinensis Spreng) fruits
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作者 Ali Abdulqader Faisal Ali +1 位作者 Amin Ismail Norhaizan Mohd Esa 《亚太热带生物医学杂志:英文版》 CAS 2019年第4期158-167,共10页
Objective: To identify and determine the composition of antioxidant compounds, and to evaluate the antioxidant abilities of Gac fruit parts(peel, pulp, seed and aril) grown in Malaysia. Methods: LC-MS/MS was used for ... Objective: To identify and determine the composition of antioxidant compounds, and to evaluate the antioxidant abilities of Gac fruit parts(peel, pulp, seed and aril) grown in Malaysia. Methods: LC-MS/MS was used for identification of antioxidant compounds and UV-Vis for estimation of the contents of phenolics, flavonoids, and carotenoids. Lycopene and β-carotene were quantified using high-performance liquid chromatography. DPPH(2, 2-diphenyl-1-picrylhydrazyl) and ferric reducing antioxidant power assays were employed to evaluate antioxidant capacities. Results: Phytochemicals were found amongst all the fruit parts. Notably, significant amounts of carotenoids [(107.4 ± 4.5),(85.7 ± 4.4),(110.6 ± 2.1) mg/100 g dry weight(DW)], and relatively high levels of both phenolics [(27.3 ± 1.7),(28.9 ± 2.4),(30.8 ± 2.7) mg/100 g DW] and flavonoids [(38.1 ± 2.2),(8.8 ± 1.3),(24.5 ± 3.3) mg/100 g DW] were found in the fruit’s peel, pulp and aril, respectively. Seed part also showed a relatively high level of flavonoids ((18.1 ± 2.3) mg/100 g DW)Lycopene and β-carotene were found to be significantly high(P < 0.05) in aril [(579.3 ± 22.7) and(621.0 ± 35.0) μg/g DW], followed by peel [(51.0 ± 7.5) and(210.0 ± 12.5) μg/g DW] and pulp ((37.6 ± 10.9) and(205.6 ± 22.1) μg/g DW))Antioxidant assays revealed that aril possessed the highest scavenging activity(IC50 = 865 μg/mL), while the peel possessed the highest ferric reducing power of 140 μmol FeSO4/μg. Conclusions: The current results demonstrate that Gac fruit grown in Malaysia is a rich source of phytochemicals, especially carotenoids, and possesses antioxidant activities. Thus, such findings suggest Gac fruit as a source of an antioxidant plant. 展开更多
关键词 Momordica cochinchinensis PHYTOCHEMICALS Carotenoids ANTIOXIDANTS POLYPHENOLS HIGH-PERFORMANCE liquid chromatography
Where there is light,there is dark:a dual process model of high-performance work systems in the eyes of employees
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作者 Xueqing Fan Yan Liu Xi Zou 《中国工商管理研究前沿:英文版》 2018年第4期424-441,共18页
High-performance work systems have been widely adopted in the workplace. Previous research on high-performance work systems debated whether the generated effects are mutual gains of conflicting outcomes for employers ... High-performance work systems have been widely adopted in the workplace. Previous research on high-performance work systems debated whether the generated effects are mutual gains of conflicting outcomes for employers and employees.Drawing on the job demands and resources model,this conceptual study proposes that high-performance work systems can be both beneficial and harmful by eliciting distinct perceptions in employees.Specifically,perceptions of job resources are the positive and perceptions of job demands are the negative mechanism whereby high-performance work systems affect employee job performance.This research further proposes that servant leadership strengthens the positive impact of high-performance work systems,whereas directive leadership strengthens the negative impact.Overall,this conceptual research provides new insights into the research on high-performance work systems. 展开更多
关键词 High-performance work system (HPWS) JOB DEMANDS JOB resources LEADERSHIP JOB performance
高性能乘法器设计 预览
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作者 周啸 代明清 《信息通信》 2018年第5期27-29,共3页
在许多实时高速信号处理中,需要使用FPGA硬件对复杂数字信号处理进行硬件加速或者预处理,例如广泛应用的矩阵求逆,方差等算法中[1],这些算法的关键都在于乘累加操作(MAC),目前的MAC操作多采用分裂式乘加器,文章设计一种高速4级流水MAC... 在许多实时高速信号处理中,需要使用FPGA硬件对复杂数字信号处理进行硬件加速或者预处理,例如广泛应用的矩阵求逆,方差等算法中[1],这些算法的关键都在于乘累加操作(MAC),目前的MAC操作多采用分裂式乘加器,文章设计一种高速4级流水MAC,对任意32bit数据进行高速的流水运算,在TSMC13工艺下进行综合,worst case下运行频率可超过400MHz。 展开更多
关键词 乘加器 流水线 压缩算法 高性能
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