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The manipulation of rectifying contact of Co and nitrogen-doped carbon hierarchical superstructures toward high-performance oxygen reduction reaction
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作者 Jing Li Tingyu Lu +6 位作者 Yu Fang Guangyao Zhou Mingyi Zhang Huan Pang Jun Yang Yawen Tang Lin Xu 《Carbon Energy》 SCIE EI CAS CSCD 2024年第9期338-349,共12页
Rational design and construction of oxygen reduction reaction(ORR)electrocatalysts with high activity,good stability,and low price are essential for the practical applications of renewable energy conversion devices,su... Rational design and construction of oxygen reduction reaction(ORR)electrocatalysts with high activity,good stability,and low price are essential for the practical applications of renewable energy conversion devices,such as metal-air batteries.Electronic modification through constructing metal/semiconductor Schottky heterointerface represents a powerful strategy to enhance the electrochemical performance.Herein,we demonstrate a concept of Schottky electrocatalyst composed of uniform Co nanoparticles in situ anchored on the carbon nanotubes aligned on the carbon nanosheets(denoted as Co@N-CNTs/NSs hereafter)toward ORR.Both experimental findings and theoretical simulation testify that the rectifying contact could impel the voluntary electron flow from Co to N-CNTs/NSs and create an internal electric field,thereby boosting the electron transfer rate and improving the intrinsic activity.As a consequence,the Co@N-CNTs/NSs deliver outstanding ORR activity,impressive long-term durability,excellent methanol tolerance,and good performance as the air-cathode in the Zn-air batteries.The design concept of Schottky contact may provide the innovational inspirations for the synthesis of advanced catalysts in sustainable energy conversion fields. 展开更多
关键词 Co-based ELECTROCATALYSTS oxygen reduction reaction rectifying CONTACT Zn-air BATTERIES
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太行山南段符山高镁闪长岩的成因——拆沉陆壳物质熔融的熔体与地幔橄榄岩反应的结果 被引量:40
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作者 许文良 杨德彬 +1 位作者 裴福萍 于洋 《岩石学报》 SCIE EI CAS CSCD 北大核心 2009年第8期1947-1961,共15页
本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。... 本文对太行山南段符山高镁闪长岩进行了年代学与地球化学研究,结合其中地幔橄榄岩包体的研究,对符山高镁闪长岩的成因和中生代岩石圈地幔的性质进行了探讨。研究表明,符山闪长岩体是由一套含橄榄石角闪闪长岩-角闪闪长岩-闪长岩构成。含橄榄岩包体的寄主岩——角闪闪长岩中的锆石可划分为两种:一是代表寄主岩浆结晶的锆石:内部结构均匀、呈条带状吸收、自形-半自形晶形,具有较高的Th/U比值(1.10~4.08),其^(206)Pb/^(238)U年龄介于123~128Ma之间,12个点的加权平均值为125±1Ma,这表明岩体的形成时代为早白垩世;二是捕获或继承锆石:具有核边结构、吸收程度不均匀、呈浑圆状和自形-半自形两种,它们的Th/U比值介于0.32~2.03之间,构成了3组^(207)Pb/^(206)Pb加权平均年龄:2503±11Ma、2181±26Ma和1778±36Ma。该类岩石的SiO_2和MgO含量分别介于56.69%~59.21%和3.60%~6.33%之间;且以高Mg~#(0.51~0.64)、富Na(Na_2O/K_2O大于1)、高Cr(93.1×10^(-6)~420×10^(-6))、Ni(35.1×10^(-6)~137×10^(-6))为特征。该类岩石强烈富集轻稀土元素和大离子亲石元素、明显亏损高场强元素,(^(87)Sr/^(86)Sr)_i、ε_(Nd)(t)值和(^(206)Pb/^(204)Pb)_i分别变化于0.70581~0.70641、-8.30~-16.56和17.052~17.512之间。综合上述特征,同时结合地慢橄榄岩包体的特征和古元古代捕获锆石的大量存在,认为符山高镁闪长岩的原始岩浆起源于拆沉陆壳物质的部分熔融,其后经历了与地幔橄榄岩的反应过程。 展开更多
关键词 North China Craton central southern continental crust partial melting peridotite XENOLITHS high field strength rare earth elements crystallization time lithospheric mantle
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Use of blood-based biomarkers for early diagnosis and surveillance of colorectal cancer 被引量:11
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作者 Ganepola AP Ganepola Joel Nizin +1 位作者 John R Rutledge David H Chang 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2014年第4期83-97,共15页
Early screening for colorectal cancer(CRC) holds the key to combat and control the increasing global burden of CRC morbidity and mortality. However, the current available screening modalities are severely inadequate b... Early screening for colorectal cancer(CRC) holds the key to combat and control the increasing global burden of CRC morbidity and mortality. However, the current available screening modalities are severely inadequate because of their high cost and cumbersome preparatory procedures that ultimately lead to a low participation rate. People simply do not like to have colonoscopies. It would be ideal, therefore, to develop an alternative modality based on blood biomarkers as the first line screening test. This will allow for the differentiation of the general population from high risk individuals. Colonoscopy would then become the secondary test, to further screen the high risk segment of the population. This will encourage participation and therefore help to reach the goal of early detection and thereby reduce the anticipated increasing global CRC incidence rate. A blood-based screening test is anappealing alternative as it is non-invasive and poses minimal risk to patients. It is easy to perform, can be repeated at shorter intervals, and therefore would likely lead to a much higher participation rate. This review surveys various blood-based test strategies currently under investigation, discusses the potency of what is available, and assesses how new technology may contribute to future test design. 展开更多
关键词 Colorectal neoplasms Early detection of cancer Colonoscopy Biological markers BLOOD Messenger RNA MicroRNA Long NON-CODING RNA DNA methylation Microsatellite instability Loss of HETEROZYGOSITY High-throughput NUCLEOTIDE sequencing Mass spectrometry Real-time polymerase chain reaction Microarray analysis
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Hepatitis C virus in human B lymphocytes transformed by Epstein-Barr virus in vitro by in situ reverse transcriptase-polymerase chain reaction 被引量:11
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作者 Ji Lin Cheng Bao Ling Liu Yi Zhang Wen Bin Tong Zheng Yan Bai Fang Feng Institute of Hepatology,Peoples Hospital,Medical Center of Beijing University,Beijing 10(X)44,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第3期370-375,共6页
AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis ... AIM: To study persistence and replication of hepatitis C virus (HCV) in patients' peripheral blood mononuclear cells (PBMC) cultured in vitro. METHODS: Epstein Barr virus (EBV) was used to transform the hepatitis C virus from a HCV positive patient to permanent lymphoblastoid cell lines (LCL). Positive and negative HCV RNA strands of the cultured cells and growth media were detected by reverse transcriptase-polymerase chain reaction (RT-PCR) each month. Core and NS5 proteins of HCV were further tested using immunohistochemical SP method and in situ RT-PCR. RESULTS: HCV RNA positive strands were consistently detected the cultured cells for one year. The negative-strand RNA in LCL cells and the positive-strand RNA in supernatants were observed intermittently. Immunohistochemical results medicated expression of HCV NS3 and C proteins in LCL cytoplasm mostly. The positive signal of PCR product was dark blue and mainly localized to the LCL cytoplasm. The RT-PCR signal was eliminated by overnight RNase digestion but not DNase digestion. CONCLUSION: HCV may exist and remain functional in a cultured cell line for a long period. 展开更多
关键词 B-LYMPHOCYTES Cells Cultured Female HEPACIVIRUS development purification Herpesvirus 4 Human Humans Immunohistochemistry In Vitro Polymerase Chain reaction RNA Viral Research Support Non-U.S. Gov't Reverse Transcriptase Polymerase Chain reaction Transformation Genetic Viral Core Proteins Viral Nonstructural Proteins Virus Replication
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Towards a new avenue for rapid synthesis of electrocatalytic electrodes via laser-induced hydrothermal reaction for water splitting
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作者 Yang Sha Menghui Zhu +6 位作者 Kun Huang Yang Zhang Francis Moissinac Zhizhou Zhang Dongxu Cheng Paul Mativenga Zhu Liu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第1期340-351,共12页
Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring ... Electrochemical production of hydrogen from water requires the development ofelectrocatalysts that are active,stable,and low-cost for water splitting.To address these challenges,researchers are increasingly exploring binder-free electrocatalytic integratedelectrodes (IEs) as an alternative to conventional powder-based electrode preparation methods,for the former is highly desirable to improve the catalytic activity and long-term stability for large-scale applications of electrocatalysts.Herein,we demonstrate a laser-inducedhydrothermal reaction (LIHR) technique to grow NiMoO4nanosheets on nickel foam,which is then calcined under H2/Ar mixed gases to prepare the IE IE-NiMo-LR.This electrode exhibits superior hydrogen evolution reaction performance,requiring overpotentials of 59,116 and143 mV to achieve current densities of 100,500 and 1000 mA·cm-2.During the 350 h chronopotentiometry test at current densities of 100 and 500 m A·cm-2,the overpotentialremains essentially unchanged.In addition,NiFe-layered double hydroxide grown on Ni foam is also fabricated with the same LIHR method and coupled with IE-NiMo-IR to achieve water splitting.This combination exhibits excellent durability under industrial current density.The energy consumption and production efficiency of the LIHR method are systematicallycompared with the conventional hydrothermal method.The LIHR method significantly improves the production rate by over 19 times,while consuming only 27.78%of the total energy required by conventional hydrothermal methods to achieve the same production. 展开更多
关键词 electrocatalytic electrode laser-induced hydrothermal reaction NiFe layered double hydroxides hydrogen evolution reaction water splitting energy consumption production rate
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Direct measurement of the break-out ^(19)F(p,γ)^(20)Ne reaction in the China Jinping underground laboratory(CJPL)
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作者 Yin‑Ji Chen Hao Zhang +28 位作者 Li‑Yong Zhang Jian‑Jun He Richard James deBoer Michael Wiescher Alexander Heger David Kahl Jun Su Daniel Odell Xin‑Yue Li Jian‑Guo Wang Long Zhang Fu‑Qiang Cao Zhi‑Cheng Zhang Xin‑Zhi Jiang Luo‑Huan Wang Zi‑Ming Li Lu‑Yang Song Liang‑Ting Sun Qi Wu Jia‑Qing Li Bao‑Qun Cui Li‑Hua Chen Rui‑Gang Ma Er‑Tao Li Gang Lian Yao‑De Sheng Zhi‑Hong Li Bing Guo Wei‑Ping Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第8期142-152,共11页
Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in astrophysics.As one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle w... Calcium production and the stellar evolution of first-generation stars remain fascinating mysteries in astrophysics.As one possible nucleosynthesis scenario,break-out from the hot carbon–nitrogen–oxygen(HCNO)cycle was thought to be the source of the calcium observed in these oldest stars.However,according to the stellar modeling,a nearly tenfold increase in the thermonuclear rate ratio of the break-out ^(19)F(p,γ)^(20) Ne reaction with respect to the competing ^(19)F(p,α)^(16) O back-processing reaction is required to reproduce the observed calcium abundance.We performed a direct measurement of this break-out reaction at the China Jinping underground laboratory.The measurement was performed down to the low-energy limit of E_(c.m.)=186 keV in the center-of-mass frame.The key resonance was observed at 225.2 keV for the first time.At a temperature of approximately 0.1 GK,this new resonance enhanced the thermonuclear ^(19)F(p,γ)^(20) Ne rate by up to a factor of≈7.4,compared with the previously recommended NACRE rate.This is of particular interest to the study of the evolution of the first stars and implies a stronger breakdown in their“warm”CNO cycle through the ^(19)F(p,γ)^(20) Ne reaction than previously envisioned.This break-out resulted in the production of the calcium observed in the oldest stars,enhancing our understanding of the evolution of the first stars. 展开更多
关键词 Nuclear astrophysics First stars Abundance of calcium reaction cross section reaction rate China Jinping underground laboratory(CJPL) JUNA
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超细层状材料A_2La_2Ti_3O_(10)(A=Na,K)的低温合成及表征 被引量:5
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作者 张莉莉 刘冠鹏 +3 位作者 张维光 陆路德 杨绪杰 汪信 《无机化学学报》 SCIE CAS CSCD 北大核心 2005年第7期1093-1097,共5页
s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalli... s: Ultrafine A2La2Ti3O10 (A=K, Na) powders with laminar structure were successfully synthesized by citric acid sol-gel method using ANO3(A=K, Na)?La(NO3)3?Ti(OBu)4 and citric acid as starting precursors. The crystalline phase of A2La2Ti3O10 can be obtained by thermal decomposition of citrate complex precursors at a relatively low temperature of 800 ℃ (600 ℃ for A=Na), about 300 ℃(500 ℃ for A=Na) lower than that of conventional solid state reaction process. The properties of the citrate precursors and the calcined powders were characterized by Infrared spectroscopy (IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), thermal-gravimetric-differential thermal analysis (TG-DTA), inductively coupled plasma (ICP) and Brunauer-Emmett-Teller (BET) techniques. Results show that the average size of A2La2Ti3O10 powders obtained by citric acid sol-gel route was reduced to 200 nm×250 nm and the specific surface area was up to 19 m2·g-1. At the same time, the product was with more regular morphological characteristics. The synthesis process and the formation of A2La2Ti3O10 were also discussed. The obtained A2La2Ti3O10 was found to be transformed from A2La2Ti3O9.5 during the formation process. 展开更多
关键词 SOL-GEL La(NO3)3 Infrared analysis complex surface process ACID plasma with the and phase solid The was SHOW area time MORE for can to be
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Atomically dispersed Fe atoms anchored on N-doped carbon hollow nanospheres boost the electrocatalytic performance for oxygen reduction reaction
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作者 Danye Liu Dong Chen Jun Yang 《Green Energy & Environment》 SCIE CSCD 2019年第3期208-209,共2页
Oxygen reduction reaction(ORR)is the key reaction at the cathode of proton exchange membrane fuel cells(PEMFCs)and metal-air batteries(1)To address the challenges associated with Pt-based electrocatalysts having promi... Oxygen reduction reaction(ORR)is the key reaction at the cathode of proton exchange membrane fuel cells(PEMFCs)and metal-air batteries(1)To address the challenges associated with Pt-based electrocatalysts having prominent activity for ORR,e.g.scarce abundance,prohibitive cost,poor stability,and vulnerability to reaction intermediates,it is necessary to explore other cost-effective ORR electrocatalysts with competitive or even superior performance to promote the commercialization of the energy conversion devices. 展开更多
关键词 Atomically dispersed FE ATOMS anchored on N-DOPED CARBON hollow NANOSPHERES BOOST the electrocatalytic performance for oxygen reduction reaction SiO BOOST
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Exciting lattice oxygen of nickel–iron bi-metal alkoxide for efficient electrochemical oxygen evolution reaction 被引量:1
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作者 Saihang Zhang Senchuan Huang +8 位作者 Fengzhan Sun Yinghui Li Li Ren Hao Xu Zhao Li Yifei Liu Wei Li Lina Chong Jianxin Zou 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期194-201,I0005,共9页
High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage systems.The electro-oxidation of water to oxygen plays a crucial role in such energy conversion te... High efficiency,cost-effective and durable electrocatalysts are of pivotal importance in energy conversion and storage systems.The electro-oxidation of water to oxygen plays a crucial role in such energy conversion technologies.Herein,we report a robust method for the synthesis of a bimetallic alkoxide for efficient oxygen evolution reaction(OER)for alkaline electrolysis,which yields current density of 10 mA cm^(-2)at an overpotential of 215 mV in 0.1 M KOH electrolyte.The catalyst demonstrates an excellent durability for more than 540 h operation with negligible degradation in activity.Raman spectra revealed that the catalyst underwent structure reconstruction during OER,evolving into oxyhydroxide,which was the active site proceeding OER in alkaline electrolyte.In-situ synchrotron X-ray absorption experiment combined with density functional theory calculation suggests a lattice oxygen involved electrocatalytic reaction mechanism for the in-situ generated nickel–iron bimetal-oxyhydroxide catalyst.This mechanism together with the synergy between nickel and iron are responsible for the enhanced catalytic activity and durability.These findings provide promising strategies for the rational design of nonnoble metal OER catalysts. 展开更多
关键词 Oxygen evolution reaction Nickel-iron bi-metal alkoxide Lattice oxygen-mediated reaction mechanism Alkaline electrolysis ELECTROCATALYSTS
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The reaction of the iron thiosulfate-nitrosyl complex with adenosine triphosphoric acid
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作者 Elena A. Saratovskikh Boris L. Psikha Natalya A. Sanina 《Natural Science》 2013年第7期800-810,共11页
Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndro... Iron tetranitrosyl complex bearing the thiosulfate ligand (TNIC) is an efficient nitrogen monoxide donor (NO). He shows antitumor properties and may be used as an original drug for the therapy of acute coronary syndrome. In this work, the reaction of the TNIC with adenosine triphosphoric acid (ATP) was studied. Formation of the products for the reaction of ATP with TNIC was shown by electronic microscopy. The kinetics of the reaction was controlled by spectrofluorometric method, and the complexation constant was measured. The mechanism of interaction of ATP with TNIC was proposed, and the relevant kinetic model satisfactorily described the experimental data, which permitted to calculate the rate constants for these process stages. NMR, IR, and M?ssbauer studies were used for determination of the reaction product structure. NMR study showed TNIC interaction only with adenine part of ATP. The method of IR spectroscopy identified both the absence NO in the reaction products and the occurrence of new Fe-S and Fe-N bonds. M?ssbauer study showed that iron in the reaction products was presented by two forms: Fe(II) and Fe(III). Thus, the structures for the [ATP-Fe2+S] and [ATP-Fe3+S] complexes were proposed. 展开更多
关键词 ADENOSINE Triphosphoric Acid Thiosulfate-Nitrosyl IRON Complex Nitrogen Monoxide Donors Fluorescence Kinetic model reaction Rate Constants Iron(II) COMPLEXES Iron(III) COMPLEXES
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Theoretical analysis of the double-differential cross-sections of neutron,proton,deuteron,^(3)He,andαfor the p+^(6) Li reaction
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作者 Fang-Lei Zou Xiao-Jun Sun +10 位作者 Jing-Shang Zhang Hai-Rui Guo Yin-Lu Han Rui-Rui Xu Xi Tao Ji-Min Wang Xiao-Dong Sun Yuan Tian Tao Ye Yong-Li Xu Chun-Tian Liang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第3期181-197,共17页
Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of l... Based on the unified Hauser–Feshbach and exciton model,which can describe the particle emission processes between discrete energy levels with energy,angular momentum,and parity conservations,a statistical theory of light nucleus reaction(STLN)is developed to calculate the double-differential cross-sections of the outgoing neutron and light charged particles for the proton-induced^(6) Li reaction.A significant difference is observed between the p+^(6) Li and p+^(7) Li reactions owing to the discrepancies in the energy-level structures of the targets.The reaction channels,including sequential and simultaneous emission processes,are analyzed in detail.Taking the double-differential cross-sections of the outgoing proton as an example,the influence of contaminations(such as^(1) H,^(7)Li,^(12)C,and^(16)O)on the target is identified in terms of the kinetic energy of the first emitted particles.The optical potential parameters of the proton are obtained by fitting the elastic scattering differential cross-sections.The calculated total double-differential cross-sections of the outgoing proton and deuteron at E_(p)=14 MeV agree well with the experimental data for different outgoing angles.Simultaneously,the mixed double differential cross-sections of^(3) He andαare in good agreement with the measurements.The agreement between the measured data and calculated results indicates that the two-body and three-body breakup reactions need to be considered,and the pre-equilibrium reaction mechanism dominates the reaction processes.Based on the STLN model,a PLUNF code for the p+^(6) Li reaction is developed to obtain an ENDF-6-formatted file of the double-differential cross-sections of the nucleon and light composite charged particles. 展开更多
关键词 Statistical theory of light nucleus reaction p%PLUS%^(6)Li reaction Light composite charged particle Double-differential cross-sections two-body breakup Three-body breakup
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燃煤固体产物中含钙矿物的迁移与多相反应 被引量:23
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作者 刘豪 邱建荣 +4 位作者 熊全军 孔凡海 张小平 王泉海 肖贤云 《中国电机工程学报》 EI CSCD 北大核心 2005年第11期72-78,共7页
燃煤灰渣中含钙矿物的组成和多相反应与灰渣活性密切相关。该文对SBF试验台上煤粉与添加剂混烧后的灰样进行XRD分析,并采用F*A*C*T软件包对煤和添加剂组成的多组分系统进行热力学计算,探讨了不同条件下灰渣中含钙矿物的组成特性。结果表... 燃煤灰渣中含钙矿物的组成和多相反应与灰渣活性密切相关。该文对SBF试验台上煤粉与添加剂混烧后的灰样进行XRD分析,并采用F*A*C*T软件包对煤和添加剂组成的多组分系统进行热力学计算,探讨了不同条件下灰渣中含钙矿物的组成特性。结果表明,燃煤灰渣中含钙矿物主要参与固相反应和固硫反应,固相反应生成的含钙矿物主要包括CaO-SiO2、CaO-Al2O3、CaO-Fe2O3以及CaO-SiO2-Al2O3类矿物。随着CaO含量的增加,灰渣中生成的最主要矿物从莫来石→钙长石→钙黄长石→硅酸二钙过渡。在CaSO4稳定存在的温度范围内,固硫反应比固相反应更易进行;随着温度的升高,CaSO4发生分解或者进一步反应生成硫铝酸钙或硫硅酸钙从而使得钙向硅酸盐矿物迁移。 展开更多
关键词 CASO4 XRD CaO
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Study on Early Warning Signals of Report on Adverse Reactions of Spontaneous Reporting System of Runzao Zhiyang Capsule
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作者 Wang Lingdi Xie Yanming +1 位作者 Wang Lianxin Zhang Chang 《World Journal of Integrated Traditional and Western Medicine》 2018年第4期44-49,共6页
Spontaneous reporting system(SRS) is an important way to monitor the adverse drug reaction(ADR) and discover the ADR signal for marketed drugs. It can detect adverse reaction signals timely and effectively, and preven... Spontaneous reporting system(SRS) is an important way to monitor the adverse drug reaction(ADR) and discover the ADR signal for marketed drugs. It can detect adverse reaction signals timely and effectively, and prevent the occurrence of drug damage. Runzao Zhiyang Capsule is mainly composed of Radix Polygoni Multiflor, Radix Polygoni Multiflori Preparata, Radix Rehmanniae Recens, Radix Sophorae Flavescentis, Folium Mori and Urtica dentata Hand.-Mazz. It has the functions of nourishing blood, nourishing yin, expelling wind to relieve itching and moistening the intestines to relieve constipation. It is mainly used for skin itching, acne, constipation and other diseases caused by blood deficiency and wind dryness. The large, national SRS database of ADRs needs effective evaluation methods. We reported on the use of Bayesian confidence propagation neural network method(BCPNN) and reporting rate ratio method(PRR) with propensity score to control confounding variables. The tendency score method was used to control the hybrid bias produced by SRS data analysis. After the calculation of PRR and BCPNN, the score of "diarrhea", "rash" and "gastric dysfunction" showed that there was an early warning before and after matching. To sum up, it indicated that diarrhea, rash and gastric dysfunction were early warning signs. 展开更多
关键词 Runzao Zhiyang CAPSULE SPONTANEOUS REPORTING system ADVERSE reactions Liver injury REPORTING rate ratio METHOD Bayesian CONFIDENCE propagation neural network METHOD
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Metal-organic-framework-derived copper-based catalyst for multicomponent C-S coupling reaction
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作者 Lixin Chen Hui Zhang +1 位作者 Linxi Hou Xin Ge 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期1-8,共8页
Copper-based metal-organic frameworks(Cu-MOFs)are a promising multiphase catalyst for catalyzing C-S coupling reactions by virtue of their diverse structures and functions.However,the unpleasant odor and instability o... Copper-based metal-organic frameworks(Cu-MOFs)are a promising multiphase catalyst for catalyzing C-S coupling reactions by virtue of their diverse structures and functions.However,the unpleasant odor and instability of the organosulfur,as well as the mass-transfer resistance that exists in multiphase catalysis,have often limited the catalytic application of Cu-MOFs in C-S coupling reactions.In this paper,a Cu-MOFs catalyst modified by cetyltrimethylammonium bromide(CTAB)was designed to enhance mass transfer by increasing the adsorption of organic substrates using the long alkanes of CTAB.Concurrently,elemental sulfur was used to replace organosulfur to achieve a highly efficient and atom-economical multicomponent C-S coupling reaction. 展开更多
关键词 Design Copper-based metal-organic frameworks (Cu-MOFs) Adsorption C-S coupling reaction Multiphase reaction
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Processing of molybdenum industrial waste into sustainable and efficient nanocatalysts for water electrolysis reactions
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作者 Federico Ursino Giacometta Mineo +6 位作者 Antonino Scandurra Mario Scuderi Angelo Forestan Catya Alba Riccardo Reitano Antonio Terrasi Salvo Mirabella 《Nano Research》 SCIE EI CSCD 2024年第11期9585-9593,共9页
The increasing need for sustainable energy and the transition from a linear to a circular economy pose great challenges to the materials science community.In this view,the chance of producing efficient nanocatalysts f... The increasing need for sustainable energy and the transition from a linear to a circular economy pose great challenges to the materials science community.In this view,the chance of producing efficient nanocatalysts for water splitting using industrial waste as starting material is attractive.Here,we report low-cost processes to convert Mo-based industrial waste powder into efficient catalysts for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER).pH controlled hydrothermal processing of Mo-based industrial waste powder leads to pure orthorhombic MoO_(3) nanobelts(50–200 nm wide,10µm long)with promising OER performances at 10 mA·cm^(−2) with an overpotential of 324 mV and Tafel slope of 45 mV·dec^(−1) in alkaline electrolyte.Indeed,MoS_(2)/MoO_(3) nanostructures were obtained after sulfurization during hydrothermal processes of the MoO_(3) nanobelts.HER tests in acidic environment show a promising overpotential of 208 mV at 10 mA·cm^(−2) and a Tafel slope of 94 mV·dec^(−1).OER and HER performances of nanocatalysts obtained from Mo industrial waste powder are comparable or better than Mo-based nanocatalysts obtained from pure commercial Mo reagent.This work shows the great potential of reusing industrial waste for energy applications,opening a promising road to join waste management and efficient and sustainable nanocatalysts for water splitting. 展开更多
关键词 MOO3 MOS2 industrial waste oxygen evolution reaction hydrogen evolution reaction critical raw material-free material
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Petrology of Spinel-Lherzolite Xenoliths from Mazéléand Others Northen Xenoliths Localities of Cameroon Volcanic Line: Exchange Reactions and Equilibrium State
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作者 Nguihdama Dagwai Kamgang Pierre +2 位作者 Mbowou Gbambié Isaac Bertrand Chazot Gilles Ngounouno Ismaïla 《Open Journal of Geology》 CAS 2024年第5期629-653,共25页
The alkaline volcanism of the Cameroon Volcanic Line in its northern domain has raised many fresh enclaves of peridotites. The samples selected come from five (05) different localities (Liri, in the plateau of Kapsiki... The alkaline volcanism of the Cameroon Volcanic Line in its northern domain has raised many fresh enclaves of peridotites. The samples selected come from five (05) different localities (Liri, in the plateau of Kapsiki, Mazélé in the NE of Ngaoundéré, Tello and Ganguiré in the SE of Ngaoundéré and Likok, locality located in the west of Ngaoundé). The peridotite enclaves of the above localities show restricted mineralogical variation. Most are four-phase spinel-lherzolites, indicating that this is the main lithology that forms the lithospheric mantle below the shallow zone. No traces of garnet or primary plagioclase were detected, which strongly limits the depth range from which the rock fragments were sampled. The textures and the wide equilibrium temperatures (884˚C - 1115˚C) indicate also entrainment of lherzolite xenoliths from shallow depths within the lithosphere and the presence of mantle diapirism. The exchange reactions and equilibrium state established in this work make it possible to characterize the chemical composition of the upper mantle of each region and test the equilibrium state of the phases between them. Variations of major oxides and incompatible elemental concentrations in clinopyroxene indicate a primary control by partial melting. The absence of typical “metasomatic” minerals, low equilibration temperatures and enriched LREE patterns indicate that the upper mantle below septentrional crust of Cameroun underwent an event of cryptic metasomatic enrichment prior to partial melting. The distinctive chemical features, LREE enrichment, strong U, Ce and Pr, depletion relative to Ba, Nb, La, Pb, and T, fractionation of Zr and Hf and therefore ligh high Zr/Hf ratio, low La/Yb, Nb/La and Ti/Eu are all results of interaction of refractory peridotite residues with carbonatite melts. 展开更多
关键词 XENOLITHS Upper Mantle Northern Region Adamawa Cameroon Volcanic Line Exchange reaction
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Study on synergistic leaching of potassium and phosphorus from potassium feldspar and solid waste phosphogypsum via coupling reactions
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作者 Chao Li Shizhao Wang +3 位作者 Yunshan Wang Xuebin An Gang Yang Yong Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期117-129,共13页
To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study invest... To achieve the resource utilization of solid waste phosphogypsum(PG)and tackle the problem of utilizing potassium feldspar(PF),a coupled synergistic process between PG and PF is proposed in this paper.The study investigates the features of P and F in PG,and explores the decomposition of PF using hydrofluoric acid(HF)in the sulfuric acid system for K leaching and leaching of P and F in PG.The impact factors such as sulfuric acid concentration,reaction temperature,reaction time,material ratio(PG/PF),liquid–solid ratio,PF particle size,and PF calcination temperature on the leaching of P and K is systematically investigated in this paper.The results show that under optimal conditions,the leaching rate of K and P reach more than 93%and 96%,respectively.Kinetics study using shrinking core model(SCM)indicates two significant stages with internal diffusion predominantly controlling the leaching of K.The apparent activation energies of these two stages are 11.92 kJ·mol^(-1)and 11.55 kJ·mol^(-1),respectively. 展开更多
关键词 PHOSPHOGYPSUM Potassium feldspar Coupling reaction LEACHING Waste treatment Kinetics
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胃肠道间质瘤60例中c-kit和PDGFRA基因突变的检测 被引量:10
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作者 贺慧颖 项一宁 +3 位作者 李燕 钟镐镐 吴秉铨 郑杰 《北京大学学报(医学版)》 CAS CSCD 北大核心 2005年第3期320-324,共5页
目的: 探讨c kit基因和PDGFRA基因在我国胃肠道间质瘤(GIST)中的突变状况。方法: 用PCR扩增和直接测序的方法,检测60例GISTc kit基因9号、11号、13号和17号外显子突变以及PDGFRA基因12号和18外显子突变。结果: 60例GIST中kit基因突变率... 目的: 探讨c kit基因和PDGFRA基因在我国胃肠道间质瘤(GIST)中的突变状况。方法: 用PCR扩增和直接测序的方法,检测60例GISTc kit基因9号、11号、13号和17号外显子突变以及PDGFRA基因12号和18外显子突变。结果: 60例GIST中kit基因突变率为63. 3%,绝大多数为杂合性突变,少数为纯合性突变。其中以编码近膜区的11号外显子突变最为常见(58. 3% );其次为编码胞外区的9号外显子突变(3. 3% );偶见编码胞内酪氨酸激酶结构域的13号外显子突变(1. 7% ),是一个新的突变位点L641P;未检出17号外显子突变。11号外显子的突变位点多集中在5′端的经典热点(42. 9% ),表现为密码子第557 -560的点突变和框内缺失。第二个热点位于11号外显子的3′端,为框内串联重复。后者主要发生在胃部,女性患者多见。60例GIST中PDGFRA基因突变率为5%,表现为编码胞内酪氨酸激酶结构域的18号外显子D842V点突变,且均为CD117阴性。未见编码近膜区的12号外显子突变。结论:CD117阳性GIST主要表现为c kit突变,分布在11号外显子经典热点和3′端热点,后者与老年女性胃GIST相关。PDGFRA基因突变主要见于CD117阴性GIST,多发生在后腹膜,具高度侵袭危险性。 展开更多
关键词 C-KIT CD117 GIST FRA PCR PDG
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Adverse drug reactions of first-line antitubercular drugs:A retrospective study on characteristics,management,factors,and impacts
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作者 Ai Ling Oh Mohd Makmor-Bakry +3 位作者 Farida Islahudin Chuo Yew Ting Swee Kim Chan Siew Teck Tie 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第10期456-464,共9页
Objective:To elucidate the characteristics,management strategies,risk factors,and clinical impacts associated with adverse drug reactions(ADRs)induced by first-line antitubercular drugs to enhance tuberculosis(TB)mana... Objective:To elucidate the characteristics,management strategies,risk factors,and clinical impacts associated with adverse drug reactions(ADRs)induced by first-line antitubercular drugs to enhance tuberculosis(TB)management.Methods:A retrospective cohort study was conducted by retrieving drug-susceptible TB records among adult patients who received TB treatment from 2018 to 2021 at 10 public health clinics in Sarawak,Malaysia.Only the initial TB treatment and occurrence of specific ADRs within the study period were considered.Regression analysis was performed to identify the risk factors associated with both overall ADRs and individual types of ADRs.Results:Among 2953 cases,705(23.9%)developed ADRs.Cutaneous reactions were the most prevalent(47.1%),followed by hepatotoxicity(32.8%)and gastrointestinal disturbances(29.8%).Six out of seven types of ADRs investigated occurred within the intensive phase,mostly manifesting at approximately 2 weeks of initiation.Hepatotoxicity resulted in the majority(85.3%)of treatment discontinuations,while vision problems led to treatment modifications in half of the cases.Risk factors for all ADRs included age≥60 years,females,illicit drug use,and comorbidities such as HIV-positive,diabetes,and chronic liver disease.Alcohol consumption was independently associated with hepatotoxicity.ADRs caused around one-third of interruptions exceeding 2 weeks(33.0%)and subsequently necessitated treatment restarts(34.5%).Conclusions:Understanding these various aspects contributes to improving the overall management of ADRs in TB treatment.Close ADR monitoring and reporting are essential to strengthen ADR management. 展开更多
关键词 Adverse events Cutaneous reactions HEPATOTOXICITY Gastrointestinal disturbances Risk factors TUBERCULOSIS
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Exploring nitrogen reduction reaction mechanisms in electrocatalytic ammonia synthesis:A comprehensive review
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作者 Abhishek Umesh Shetty Ravi Sankannavar 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期681-697,共17页
The electrochemical nitrogen reduction reaction(eNRR)holds significant promise as a sustainable alternative to the conventional large-scale Haber Bosch process,offering a carbon footprint-free approach for ammonia syn... The electrochemical nitrogen reduction reaction(eNRR)holds significant promise as a sustainable alternative to the conventional large-scale Haber Bosch process,offering a carbon footprint-free approach for ammonia synthesis.While the process is thermodynamically feasible at ambient temperature and pressure,challenges such as the competing hydrogen evolution reaction,low nitrogen solubility in electrolytes,and the activation of inert dinitrogen(N_(2))gas adversely affect the performance of ammonia production.These hurdles result in low Faradaic efficiency and low ammonia production rate,which pose obstacles to the commercialisation of the process.Researchers have been actively designing and proposing various electrocatalysts to address these issues,but challenges still need to be resolved.A key strategy in electrocatalyst design lies in understanding the underlying mechanisms that govern the success or failure of the electrocatalyst in driving the electrochemical reaction.Through mechanistic studies,we gain valuable insights into the factors affecting the reaction,enabling us to propose optimised designs to overcome the barriers.This review aims to provide a comprehensive understanding of the various mechanisms involved in eNRR on the electrocatalyst surface.It delves into the various mechanisms such as dissociative,associative,Mars-van Krevelen,lithium-mediated nitrogen reduction and surface hydrogenation mechanisms of nitrogen reduction.By unravelling the intricacies of eNRR mechanisms and exploring promising avenues,we can pave the way for more efficient and commercially viable ammonia synthesis through this sustainable electrochemical process by designing an efficient electrocatalyst. 展开更多
关键词 Green ammonia synthesis ELECTROLYSIS ELECTROCATALYSIS Nitrogen reductionreaction Electrochemical reaction pathways reactionMECHANISM
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