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Research on Preparation and Electrochemical Performance of the High Compacted Density Ni-Co-Mn Ternary Cathode Materials
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作者 Fupeng Zhi Juanhui Wang +1 位作者 xiaomin zhang Jun zhang 《Advances in Materials Physics and Chemistry》 CAS 2024年第3期47-53,共7页
The high compacted density LiNi<sub>0.5-x</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub>Mg<sub>x</sub>O<sub>2</sub> cathode material for lithium-ion batteries was syn... The high compacted density LiNi<sub>0.5-x</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub>Mg<sub>x</sub>O<sub>2</sub> cathode material for lithium-ion batteries was synthesized by high temperature solid-state method, taking the Mg element as a doping element and the spherical Ni<sub>0.5</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub> (OH)<sub>2</sub>, Li<sub>2</sub>CO<sub>3</sub> as raw materials. The effects of calcination temperature on the structure and properties of the products were investigated. The structure and morphology of cathode materials powder were analyzed by X-ray diffraction spectroscopy (XRD) and scanning electronmicroscopy (SEM). The electrochemical properties of the cathode materials were studied by charge-discharge test and cyclic properties test. The results show that LiNi<sub>0.4985</sub>Co<sub>0.2</sub>Mn<sub>0.3</sub> Mg<sub>0.0015</sub>O<sub>2</sub> cathode material prepared at calcination temperature 930°C has a good layered structure, and the compacted density of the electrode sheet is above 3.68 g/cm<sup>3</sup>. The discharge capacity retention rate is more than 97.5% after 100 cycles at a charge-discharge rate of 1C, displaying a good cyclic performance. 展开更多
关键词 High Compacted Density Ternary Cathode Materials Electrochemical Performance
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SSZ-13分子筛在二甲醚羰基化反应中的机理研究和空间限域效应
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作者 张晓敏 蔡凯 +6 位作者 李媖 戚暨 王悦 刘云铎 王美岩 黄守莹 马新宾 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第6期301-311,共11页
乙醇作为一种绿色清洁的燃料替代品和油品添加剂,在全球有广泛的市场需求.利用合成气经乙酸甲酯(MA)合成乙醇的工艺路线,因其原子经济性、产品选择性高、反应条件温和等优势而备受关注.其中,二甲醚(DME)羰基化是该路线的关键步骤之一.... 乙醇作为一种绿色清洁的燃料替代品和油品添加剂,在全球有广泛的市场需求.利用合成气经乙酸甲酯(MA)合成乙醇的工艺路线,因其原子经济性、产品选择性高、反应条件温和等优势而备受关注.其中,二甲醚(DME)羰基化是该路线的关键步骤之一.研究证实,具有8元环(8-MR)孔道结构的硅铝酸盐微孔分子筛可以在较低的反应温度下高选择性催化二甲醚羰基化反应.目前,研究者已经对丝光沸石(MOR)、镁碱沸石(FER)等分子筛进行了全面深入的分析,但对SSZ-13等菱沸石(CHA型)的研究有限,缺乏SSZ-13上主、副反应催化机理的阐释,并且忽略了沸石独特的笼状结构在反应中的空间限域效应.本文结合实验和理论计算确定了SSZ-13分子筛催化DME羰基化的活性位点,并探究了孔道的限域效应.通过负载具有不同尺寸的Na^(+)和Cs^(+)实现了对不同通道中Brönsted酸位点(BAS)的选择性屏蔽.酸性质表征和密度泛函理论(DFT)计算结果表明,在较低的负载量下,Na^(+)优先取代SSZ-13的6元环(6-MR)中的BAS,而Cs^(+)由于其较大的离子半径只能与8-MR中的BAS发生交换,从而实现了对SSZ-13不同孔道中酸分布的调控.负载不同金属量以及金属种类的样品活性研究表明,当6-MR中BAS减少时,DME转化率基本不变;而当8-MR中BAS被离子交换时,DME转化率明显下降.随后,将未经金属改性的、具有不同硅铝比的母体SSZ-13样品的MA生成速率与其8-MR中BAS的数量相关联,发现两者呈较好的线性关系,说明SSZ-13的8-MR中BAS为DME羰基化的活性中心.同时,DFT计算了DME在不同孔道BAS上的解离能,结果表明DME更容易在8-MR的BAS上解离从而进行后续反应.随后,探究了SSZ-13笼的空间限域效应对主副反应的影响机制.通过比较金属负载量相近的Na/H-SSZ-13和Cs/H-SSZ-13上CO插入甲氧基形成烯酮的反应势垒,证实了较大尺寸金属离子的引入增加了主反应速控步的能垒.为了揭示空间限域对副反应的影响,比较了反应后催化剂的热重、气质联用等表征结果,并利用密度泛函理论计算了副反应的关键物种(七甲基苯正离子)在Na/H-SSZ-13和Cs/H-SSZ-13上的吸附能,证实了SSZ-13的笼状结构体积是影响MA选择性的关键因素.金属负载后SSZ-13笼空间减少,可以有效地抑制副反应关键物种的形成,从而提高主反应选择性.综上,本文不仅对SSZ-13分子筛催化二甲醚羰基化反应机理进行了全面解析,并通过实验设计,改变了SSZ-13分子筛的孔道结构和笼结构空间,突出了分子筛限域效应在二甲醚羰基化反应中的重要作用.本文研究结果为设计具有较高选择性的沸石催化剂提供一定的参考. 展开更多
关键词 二甲醚 羰基化 SSZ-13分子筛 酸位点 限域效应
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Giant Magneto-Optical Effect in van der Waals Room-Temperature Ferromagnet Fe_(3)GaTe_(2)
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作者 张晓敏 王健 +4 位作者 朱文凯 张佳茜 李伟浩 张菁 王开友 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期148-155,共8页
The discovery of ferromagnetic two-dimensional(2D)van der Waals(vdWs)materials provides an opportunity to explore intriguing physics and to develop innovative spin electronic devices.However,the main challenge for pra... The discovery of ferromagnetic two-dimensional(2D)van der Waals(vdWs)materials provides an opportunity to explore intriguing physics and to develop innovative spin electronic devices.However,the main challenge for practical applications of vd Ws ferromagnetic crystals lies in the weak intrinsic ferromagnetism and small perpendicular magnetic anisotropy(PMA)above room temperature.Here,we report the intrinsic vd Ws ferromagnetic crystal Fe_(3)GaTe_(2),synthesized by the self-flux method,exhibiting a Curie temperature(TC)of 370 K,a high saturation magnetization of 33.47 emu/g,and a large PMA energy density of approximately 4.17×10^(5)J/m^(3).Furthermore,the magneto-optical effect is systematically investigated in Fe_(3)GaTe_(2).The doubly degenerate E_(2g)(Γ)mode reverses the helicity of incident photons,indicating the existence of pseudoangular-momentum(PAM)and chirality.Meanwhile,the non-degenerate non-chiral A_(1g)(Γ)phonon exhibits a significant magneto-Raman effect under an external out-of-plane magnetic field.These results lay the groundwork for studying phonon chirality and magneto-optical phenomena in 2D magnetic materials,providing the feasibility for further fundamental research and applications in spintronic devices. 展开更多
关键词 field FERROMAGNETIC DEGENERATE
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Genome-wide association study identifies novel candidate loci or genes affecting stalk strength in maize 被引量:1
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作者 Shuhui Xu Xiao Tang +5 位作者 xiaomin zhang Houmiao Wang Weidong Ji Chenwu Xu Zefeng Yang Pengcheng Li 《The Crop Journal》 SCIE CSCD 2023年第1期220-227,共8页
Stalk strength increases resistance to stalk lodging,which causes maize(Zea mays L.)production losses worldwide.The genetic mechanisms regulating stalk strength remain unclear.In this study,three stalk strength-relate... Stalk strength increases resistance to stalk lodging,which causes maize(Zea mays L.)production losses worldwide.The genetic mechanisms regulating stalk strength remain unclear.In this study,three stalk strength-related traits(rind penetrometer resistance,stalk crushing strength,and stalk bending strength)and four plant architecture traits(plant height,ear height,stem diameter,stem length)were measured in three field trials.Substantial phenotypic variation was detected for these traits.A genome-wide association study(GWAS)was conducted using general and mixed linear models and 372,331 single-nucleotide polymorphisms(SNPs).A total of 94 quantitative trait loci including 241 SNPs were detected.By combining the GWAS data with public gene expression data,56 candidate genes within 50 kb of the significant SNPs were identified,including genes encoding flavonol synthase(GRMZM2G069298,ZmFLS2),nitrate reductase(GRMZM5G878558,ZmNR2),glucose-1-phosphate adenylyltransferase(GRMZM2G027955),and laccase(GRMZM2G447271).Resequencing GRMZM2G069298 and GRMZM5G878558 in all tested lines revealed respectively 47 and 2 variants associated with RPR.Comparison of the RPR of the zmnr2EMS mutant and the wild-type plant under high-and low-nitrogen conditions verified the GRMZM5G878558 function.These findings may be useful for clarifying the genetic basis of stalk strength.The identified candidate genes and variants may be useful for the genetic improvement of maize lodging resistance. 展开更多
关键词 Stalk strength MAIZE GWAS Candidate genes Lodging resistance
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Negative-to-Positive Tunnel Magnetoresistance in van der Waals Fe_(3)GeTe_(2)/Cr_(2)Ge_(2)Te_(6)/Fe_(3)GeTe_(2)Junctions
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作者 王子奥 张晓敏 +4 位作者 朱文凯 闫法光 刘鹏飞 袁喆 王开友 《Chinese Physics Letters》 SCIE EI CAS CSCD 2023年第7期51-55,共5页
The emergent van der Waals magnetic material is a promising component for spintronic devices with novel functionalities.Here,we report a transition of negative-to-positive magnetoresistance in Fe_(3)GeTe_(2)/Cr_(2)Ge_... The emergent van der Waals magnetic material is a promising component for spintronic devices with novel functionalities.Here,we report a transition of negative-to-positive magnetoresistance in Fe_(3)GeTe_(2)/Cr_(2)Ge_(2)Te_(6)/Fe_(3)GeTe_(2)van der Waals all-magnetic tunnel junctions with increasing the applied bias voltage.A negative magnetoresistance is observed first in Fe_(3)GeTe_(2)/Cr_(2)Ge_(2)Te_(6)/Fe_(3)GeTe_(2)tunnel junctions,where the resistance with antiparallel aligned magnetization of two Fe_(3)GeTe_(2)electrodes is lower than that with parallel alignment,which is due to the opposite spin polarizations of two Fe_(3)GeTe_(2)electrodes.With the bias voltage increasing,the spin polarization of the biased Fe_(3)GeTe_(2)electrode is changed so that the spin orientations of two Fe_(3)GeTe_(2)electrodes are the same.Our experimental observations are supported by the calculated spin-dependent density of states for Fe_(3)GeTe_(2)electrodes under a finite bias.The significantly bias voltage-dependent spin transport properties in van der Waals magnetic tunnel junctions open a promising route for designing electrical controllable spintronic devices based on van der Waals magnets. 展开更多
关键词 (3) ALIGNMENT opposite
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中国与“一带一路”沿线国家跨国科学研究合作何以可能?——一项定性比较分析 被引量:3
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作者 阎波 陈斌 +2 位作者 武龙 张晓敏 韩东伶 《公共行政评论》 CSSCI 北大核心 2021年第2期174-194,233,234,共23页
【问题】中国与“一带一路”沿线国家之间的跨国科学研究合作是承载“一带一路”建设科技交流与创新发展使命的重要议题,然而由于许多“一带一路”沿线国家的制度和法律环境尚不健全,甚至部分国家还存在较强的政治风险和文化冲突,这种... 【问题】中国与“一带一路”沿线国家之间的跨国科学研究合作是承载“一带一路”建设科技交流与创新发展使命的重要议题,然而由于许多“一带一路”沿线国家的制度和法律环境尚不健全,甚至部分国家还存在较强的政治风险和文化冲突,这种合作并非易事。在此背景下,中国与“一带一路”沿线国家之间的跨国科学研究合作何以成为可能?【方法】本研究从宏观分析视角提出了中国与“一带一路”沿线国家之间跨国科学研究合作影响因素的分析框架,并采用模糊集定性比较分析方法识别了36个沿线国家案例中的跨国科学研究合作影响因素及其条件组合。【发现】资源投入与制度环境是影响跨国科学研究合作的重要因素,两者相互耦合共同构成跨国科学研究合作的实现路径。进一步地,本研究依据资源投入与制度环境不同耦合程度,识别出强强联合型、资源主导型、经贸带动型与政治兜底型四种跨国科学研究合作类型。【贡献】论文提出的分析框架弥补了以往研究聚焦于中观和微观层面跨国科学研究合作影响因素分析的局限性,区分了不同伙伴国家与中国开展跨国科学研究合作的各种途径,可以更为准确地解释全球治理背景下的跨国科学研究合作机制,对于中国进一步深入推进与沿线国家之间的跨国科学研究合作、提升合作效果具有积极意义。 展开更多
关键词 “一带一路”倡议 跨国科学研究合作 定性比较分析 创新
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低剂量螺旋CT在肺癌筛查中的应用 被引量:12
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作者 孔令芹 张晓敏 +1 位作者 李西川 苏延军 《中国肺癌杂志》 CAS CSCD 北大核心 2022年第9期678-683,共6页
肺癌是全世界发病率和死亡率最高的恶性肿瘤之一,患者的早期诊断率低、预后差,已造成严重的社会负担。通过低剂量螺旋计算机断层扫描(low-dose spiral computed tomography,LDCT)对高危人群进行定期筛查的方法能够显著提高肺癌的早期诊... 肺癌是全世界发病率和死亡率最高的恶性肿瘤之一,患者的早期诊断率低、预后差,已造成严重的社会负担。通过低剂量螺旋计算机断层扫描(low-dose spiral computed tomography,LDCT)对高危人群进行定期筛查的方法能够显著提高肺癌的早期诊断率,为肺癌的诊疗带来了新机遇。近年来,全世界多个国家开展了LDCT肺癌筛查项目并取得了良好的效果,但在筛查主体的选择、筛查频率、成本效能等方面也存在一些争议。本文将从LDCT肺癌筛查的关键因素、筛查效果、肺结节的管理和人工智能对于LDCT的发展贡献等方面进行综述,探讨LDCT在肺癌筛查中的应用进展。 展开更多
关键词 肺肿瘤 低剂量螺旋计算机断层扫描 筛查 早诊 肺结节管理
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Risk factors and long-term health consequences of macrosomia:a prospective study in Jiangsu Province,China 被引量:14
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作者 Shouyong Gu Xiaofei An +9 位作者 Liang Fang xiaomin zhang Chunyan zhang Jingling Wang Qilan Liu Yanfang zhang Yongyue Wei Zhibin Hu Feng Chen Hongbing Shen 《The Journal of Biomedical Research》 CAS 2012年第4期235-240,共6页
We sought to determine risk factors associated with fetal macrosomia and to explore the long-term consequence of infant macrosomia at the age of 7 years.A prospective population based cohort study was designed to exam... We sought to determine risk factors associated with fetal macrosomia and to explore the long-term consequence of infant macrosomia at the age of 7 years.A prospective population based cohort study was designed to examine the associations between maternal and perinatal characteristics and the risk of macrosomia.A nested case-control study was conducted to explore the long-term health consequence of infant macrosomia.The mean maternal age of the macrosomia group was 24.74±3.32 years,which is slightly older than that in the control group(24.35±3.14 years,P = 0.000).The mean maternal body mass index(BMI) at early pregnancy was 22.75±2.81 kg/m 2,which was also higher than that in the control group(21.76±2.59 kg/m 2,P = 0.000).About 64.6% of macrosomic neonates were males,compared with 51.0% in the control group(P = 0.000).Compared with women with normal weight(BMI:18.5-23.9 kg/m 2),women who were overweight(BMI:24-27.9 kg/m 2) or obese(BMI ≥ 28 kg/m 2),respectively,had a 1.69-fold(P = 0.000) and a 1.49-fold(P = 0.000) increased risks of having a neonate with macrosomia,while light weight(BMI〈18.5 kg/m 2) women had an approximately 50% reduction of the risk.Furthermore,macrosomia infant had a 1.52-fold and 1.50-fold risk,respectively,of developing overweight or obesity at the age of 7 years(P = 0.001 and P = 0.000).Older maternal age,higher maternal BMI at early pregnancy and male gender were independent risk factors of macrosomia.Macrosomic infant was associated with an increased predisposition to develop overweight or obesity at the beginning of their childhood. 展开更多
关键词 risk factors LONG-TERM health consequences MACROSOMIA
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Improving the performance of solid oxide electrolysis cell with gold nanoparticles-modified LSM-YSZ anode 被引量:5
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作者 Yuefeng Song xiaomin zhang +5 位作者 Yingjie Zhou Houfu Lv Qingxue Liu Weicheng Feng Guoxiong Wang Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第8期181-187,I0007,共8页
Gold, as the common current collector in solid oxide electrolysis cell(SOEC), is traditionally considered to be inert for oxygen evolution reaction at the anode of SOEC. Herein, gold nanoparticles were loaded onto con... Gold, as the common current collector in solid oxide electrolysis cell(SOEC), is traditionally considered to be inert for oxygen evolution reaction at the anode of SOEC. Herein, gold nanoparticles were loaded onto conventional strontium doped lanthanum manganite-yttria stabilized zirconia(LSM-YSZ) anode, which evidently improved the performance of oxygen evolution reaction at 800 °C. The current densities at 1.2 V and 1.4 V increased by 60.0% and 46.9%, respectively, after loading gold nanoparticles onto the LSM-YSZ anode. Physicochemical characterizations and electrochemical measurements suggested that the improved SOEC performance was attributed to the accelerated electron transfer of elementary process in anodic polarization reaction and the newly generated triple phase boundaries in gold nanoparticles-loaded LSMYSZ anode. 展开更多
关键词 Solid oxide ELECTROLYSIS cell Oxygen evolution reaction Gold nanoparticles CO2 ELECTROLYSIS STRONTIUM doped LANTHANUM manganite-yttria stabilized zirconia
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Co-electrolysis of CO_2 and H_2O in high-temperature solid oxide electrolysis cells: Recent advance in cathodes 被引量:7
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作者 xiaomin zhang Yuefeng Song +1 位作者 Guoxiong Wang Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第5期839-853,共15页
Co-electrolysis of CO2and H2O using high-temperature solid oxide electrolysis cells(SOECs) into valuable chemicals has attracted great attentions recently due to the high conversion and energy efficiency,which provide... Co-electrolysis of CO2and H2O using high-temperature solid oxide electrolysis cells(SOECs) into valuable chemicals has attracted great attentions recently due to the high conversion and energy efficiency,which provides opportunities of reducing CO2emission, mitigating global warming and storing intermittent renewable energies. A single SOEC typically consists of an ion conducting electrolyte, an anode and a cathode where the co-electrolysis reaction takes place. The high operating temperature and difficult activated carbon-oxygen double-bond of CO2put forward strict requirements for SOEC cathode. Great efforts are being devoted to develop suitable cathode materials with high catalytic activity and excellent long-term stability for CO2/H2O electro-reduction. The so far cathode material development is the key point of this review and alternative strategies of high-performance cathode material preparation is proposed. Understanding the mechanism of CO2/H2O electro-reduction is beneficial to highly active cathode design and optimization. Thus the possible reaction mechanism is also discussed. Especially, a method in combination with electrochemical impedance spectroscopy(EIS) measurement, distribution functions of relaxation times(DRT) calculation, complex nonlinear least square(CNLS) fitting and operando ambient pressure X-ray photoelectron spectroscopy(APXPS) characterization is introduced to correctly disclose the reaction mechanism of CO2/H2O co-electrolysis. Finally, different reaction modes of the CO2/H2O coelectrolysis in SOECs are summarized to offer new strategies to enhance the CO2conversion. Otherwise,developing SOECs operating at 300-600 °C can integrate the electrochemical reduction and the Fischer-Tropsch reaction to convert the CO2/H2O into more valuable chemicals, which will be a new research direction in the future. 展开更多
关键词 SOECs Co-electrolysis Carbon dioxide STEAM CATHODE
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Infiltration of Ce0.8Gd0.2O1.9 nanoparticles on Sr2Fe1.5Mo0.5O6-δ cathode for CO2 electroreduction in solid oxide electrolysis cell 被引量:5
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作者 Houfu Lv Yingjie Zhou +4 位作者 xiaomin zhang Yuefeng Song Qingxue Liu Guoxiong Wang Xinhe Bao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第8期71-78,I0004,共9页
Solid oxide electrolysis cell(SOEC) can electrochemically convert CO2 to CO at the gas-solid interface with a high current density and Faradaic efficiency, which has attracted increasing attentions in recent years.Exp... Solid oxide electrolysis cell(SOEC) can electrochemically convert CO2 to CO at the gas-solid interface with a high current density and Faradaic efficiency, which has attracted increasing attentions in recent years.Exploring efficient catalyst for electrochemical CO2 reduction reaction(CO2 RR) at the cathode is a grand challenge for the research and development of SOEC. Sr2Fe1.5Mo0.5O6-δ(SFM) is one kind of promising cathode materials for SOEC, but suffers from insufficient activity for CO2 RR. Herein, Gd0.2Ce0.8O1.9(GDC)nanoparticles were infiltrated onto the SFM surface to construct a composite GDC-SFM cathode and improve the CO2 RR performance in SOEC. The current density over the GDC infiltrated SFM cathode with a GDC loading of 12.8 wt% reaches 0.446 A cm-2 at 1.6 V and 800 °C, which is much higher than that over the SFM cathode(0.283 A cm-2). Temperature-programmed desorption of CO2 measurements suggest that the infiltration of GDC nanoparticles significantly increases the density of surface active sites and three phase boundaries(TPBs), which are beneficial for CO2 adsorption and subsequent conversion. Electrochemical impedance spectroscopy results indicate that the polarization resistance of 12.8 wt% GDCSFM cathode was obviously decreased from 0.46 to 0.30 cm^2 after the infiltration of GDC nanoparticles. 展开更多
关键词 Electrochemical carbon dioxide reduction reaction Solid oxide ELECTROLYSIS cell Double PEROVSKITE INFILTRATION
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A novel proton-gradient-transfer acid complexes as an efficient and reusable catalyst for fatty acid esterification 被引量:3
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作者 xiaomin zhang Wenjie Xiong +3 位作者 Zengyu Yin Yongle Chen Youting Wu Xingbang Hu 《Green Energy & Environment》 SCIE EI CSCD 2022年第1期137-144,共8页
In this work,a series of novel proton-gradient-transfer acid complexes(PGTACs)were developed.Their physicochemical properties,including thermal stability,melting point,and Hammett acidity,were measured.The effects of ... In this work,a series of novel proton-gradient-transfer acid complexes(PGTACs)were developed.Their physicochemical properties,including thermal stability,melting point,and Hammett acidity,were measured.The effects of catalyst loading,reaction temperature,and substrate expansion on the catalytic performance were systematically studied.It is found that the combination of bidentate N-heterocycle and H;SO;(1:2 M ratio)could form simultaneously N–H covalent bond and N…H hydrogen bond,which makes the PGTACs excellent catalysts integrate the advantages of strong acids(high catalytic activity)and ionic liquids(phase separation)in the esterification reaction.Moreover,these PGTACs can be reused by convenient phase separation without obvious diminution of catalytic activity.It is concluded that these PGTACs are potential alternative candidates for esterification reaction in the process of industrial catalysis. 展开更多
关键词 Proton-gradient-transfer Hydrogen bond CATALYSIS ESTERIFICATION Self-separation
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Large Room-Temperature Magnetoresistance in van der Waals Ferromagnet/Semiconductor Junctions 被引量:4
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作者 Wenkai Zhu Shihong Xie +15 位作者 Hailong Lin Gaojie zhang Hao Wu Tiangui Hu Ziao Wang xiaomin zhang Jiahan Xu Yujing Wang Yuanhui Zheng Faguang Yan Jing zhang Lixia Zhao Amalia Patanè Jia zhang Haixin Chang Kaiyou Wang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2022年第12期99-103,共5页
A magnetic tunnel junction(MTJ)is the core component in memory technologies,such as the magnetic random-access memory,magnetic sensors and programmable logic devices.In particular,MTJs based on twodimensional van der ... A magnetic tunnel junction(MTJ)is the core component in memory technologies,such as the magnetic random-access memory,magnetic sensors and programmable logic devices.In particular,MTJs based on twodimensional van der Waals(vd W)heterostructures offer unprecedented opportunities for low power consumption and miniaturization of spintronic devices.However,their operation at room temperature remains a challenge.Here,we report a large tunnel magnetoresistance(TMR)of up to 85%at room temperature(T=300 K)in vdW MTJs based on a thin(<10 nm)semiconductor spacer WSe_(2)layer embedded between two Fe_(3)GaTe_(2e)lectrodes with intrinsic above-room-temperature ferromagnetism.The TMR in the MTJ increases with decreasing temperature up to 164%at T=10 K.The demonstration of TMR in ultra-thin MTJs at room temperature opens a realistic and promising route for next-generation spintronic applications beyond the current state of the art. 展开更多
关键词 RESISTANCE SPACER TUNNEL
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Preparation and Properties of Bio-Based Flame Retardant Polyvinyl Alcohol 被引量:3
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作者 You Shu Qionglin Luo +4 位作者 Hongwei Lin Yuejun Ouyang xiaomin zhang Liping Sheng Shengpei Su 《Journal of Renewable Materials》 SCIE EI 2021年第5期909-921,共13页
Polyvinyl alcohol (PVA) has been widely used in the fields of medical, food and packaging due to its excellentbiocompatibility, good fiber-forming and film-forming properties. However, the high flammability of PVA has... Polyvinyl alcohol (PVA) has been widely used in the fields of medical, food and packaging due to its excellentbiocompatibility, good fiber-forming and film-forming properties. However, the high flammability of PVA hasgreatly limited its wider applications. The flame-retardant PVA was prepared by melt blending of a bio-basedflame retardant (prepared from lignin, phosphoric acid and carbamide) with thermoplastic PVA (TPVA). Thechemical structure, morphology, thermal properties, mechanical properties, fire property and fluidity of thisflame retardant PVA were investigated by Fourier transform infrared spectrometer(FTIR), field emission scanning electron microscope(SEM), thermogravimetric analyzer(TGA), impact tester, universal testing machine,horizontal-vertical burning tester, limiting oxygen indexer(LOI) and melt flow rate meter(MFR). The resultsshowed that the prepared flame retardant had good compatibility with the PVA substrate;The impact strength,melt flow rate, fire property and char residue of this PVA material increased with the content of bio-based flameretardant. When the content of flame retardant was of 20%, the five indices including impact strength, meltflow rate, UL-94 level, LOI and char residual were 11.3 KJ/m^(2), 21.2 g/10 min, V-0 UL-94 level, 33.1%, and19.2%, respectively. This research can promote the high-value utilization of lignin and the application ofPVA in the fields of fire protection. 展开更多
关键词 Bio-based flame retardant LIGNIN ammonium polyphosphate polyvinyl alcohol
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Role of Nanfan Base and Recommendations about Construction and Management 被引量:3
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作者 Hongbo DUAN Yang DAI +2 位作者 Xiangping LIU Zhixin LI xiaomin zhang 《Asian Agricultural Research》 2015年第12期34-36,共3页
This paper first analyzes the important role of Nanfan Base in China: " accelerator" for breeding new varieties of crops; " unallocated store" to ensure the varieties for agricultural production; &... This paper first analyzes the important role of Nanfan Base in China: " accelerator" for breeding new varieties of crops; " unallocated store" to ensure the varieties for agricultural production; " lightning rod" to ensure the quality and safety of seeds; " big stage" for variety and technical exchanges and cooperation; " big school" for cultivating seed industry technology talents; " booster" for promoting local economic development. Then it points out the main problems about Nanfan Base and finally sets forth the relevant recommendations. 展开更多
关键词 Nanfan BASE Important ROLE MAIN PROBLEMS Construction and MANAGEMENT RECOMMENDATIONS
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液体活检在小细胞肺癌诊疗中的应用研究进展 被引量:1
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作者 张晓敏 徐梦圆 +1 位作者 李西川 苏延军 《中国肺癌杂志》 CAS CSCD 北大核心 2022年第8期609-614,共6页
小细胞肺癌(small cell lung cancer,SCLC)是一种侵袭性强、死亡率高的恶性肿瘤,具有易转移、生长速度快、恶性程度高和侵袭性强等特点,患者预后一般较差。目前SCLC的临床诊断方法主要以组织活检为主,创伤大、周期长且成本高。近年来,... 小细胞肺癌(small cell lung cancer,SCLC)是一种侵袭性强、死亡率高的恶性肿瘤,具有易转移、生长速度快、恶性程度高和侵袭性强等特点,患者预后一般较差。目前SCLC的临床诊断方法主要以组织活检为主,创伤大、周期长且成本高。近年来,液体活检以传统组织活检所不具备的无创性、全面性、实时性等优良特点而逐渐获得应用。液体活检的主要检测对象包括外周血中的循环肿瘤DNA(circulating tumor DNA,ctDNA)、循环肿瘤细胞(circulating tumors cells,CTCs)及外泌体等。将液体活检应用于SCLC的临床治疗,有助于提高临床医生对SCLC患者病情的详细诊断,以及对患者治疗反应的及时掌控和应对。 展开更多
关键词 肺肿瘤 液体活检 循环肿瘤DNA 循环肿瘤细胞 外泌体
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Highly dispersed nickel species on iron‐based perovskite for CO_(2) electrolysis in solid oxide electrolysis cell 被引量:1
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作者 Yingjie Zhou Tianfu Liu +5 位作者 Yuefeng Song Houfu Lv Qingxue Liu Na Ta xiaomin zhang Guoxiong Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第7期1710-1718,共9页
Feasible construction of cathode materials with highly dispersed active sites can extend the tri‐ple‐phase boundaries,and therefore leading to enhanced electrode kinetics for CO_(2) electrolysis in solid oxide elect... Feasible construction of cathode materials with highly dispersed active sites can extend the tri‐ple‐phase boundaries,and therefore leading to enhanced electrode kinetics for CO_(2) electrolysis in solid oxide electrolysis cell(SOEC).Herein,highly dispersed nickel species with low loading(1.0 wt%)were trapped within the La_(0.8)Sr_(0.2)FeO_(3)–δ‐Ce_(0.8)Sm_(0.2)O_(2)–δvia a facial mechanical milling ap‐proach,which demonstrated excellent CO_(2) electrolysis performance.The highly dispersed nickel species can significantly alter the electronic structures of the LSF‐SDC without affecting its porous network and facilitate oxygen vacancy formation,thus greatly promote the CO_(2) electrolysis perfor‐mance.The highest current density of 1.53 A·cm^(-2) could be achieved when operated under 800℃ at 1.6 V,which is about 91%higher than the LSF‐SDC counterpart. 展开更多
关键词 CO_(2)electrolysis Solid oxide electrolysis cells Perovskite oxide Nickel species
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山西猪场猪蓝耳病并发猪胸膜肺炎放线杆菌的病毒鉴定及细菌分离鉴定以及治疗方案 被引量:5
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作者 张小敏 郭波 +4 位作者 段宝敏 冯敬敬 李嘉 雷向东 陈家锃 《猪业科学》 2020年第5期84-87,共4页
2020年2月份山西某大型规模猪场育肥猪突发呼吸困难,无过多症状表现,即突然死亡,发病率为2%,死亡率1.5%左右。实验室以病死猪为研究对象,综合死亡猪只脏器病变状况观察,无菌采集病死猪的肺脏、肝脏、脾脏病料,进行RT-PCR检测猪蓝耳病原... 2020年2月份山西某大型规模猪场育肥猪突发呼吸困难,无过多症状表现,即突然死亡,发病率为2%,死亡率1.5%左右。实验室以病死猪为研究对象,综合死亡猪只脏器病变状况观察,无菌采集病死猪的肺脏、肝脏、脾脏病料,进行RT-PCR检测猪蓝耳病原;用含1%NAD和5%胎牛血清的TSA琼脂培养基进行细菌分离培养和纯化,经形态学鉴定、PCR鉴定、16Sr RNA基因序列进化树构建等方法,结果显示:该发病猪群为猪繁殖与呼吸障碍综合征并发猪胸膜肺炎放线杆菌感染。药敏试验结果显示:该猪胸膜肺炎放线杆菌对安普霉素、硫酸黏菌素、替米考星+氟苯尼考、替米考星+阿莫西林、氟苯尼考、头孢噻呋钠+硫酸黏菌素、头孢喹肟、头孢噻呋钠+新霉素、替米考星+头孢噻呋钠、多西环素+氟苯尼考、头孢噻呋钠+阿莫西林、阿莫西林+克拉维酸钾、头孢噻呋钠+恩诺沙星、新霉素、头孢噻呋钠、安普霉素+头孢噻呋钠敏感。对恩诺沙星耐药。本实验室根据临床及检测结果制定治疗方案,为该猪场的猪繁殖与呼吸障碍综合征并发猪胸膜肺炎的临床诊断及用药提供了理论依据。 展开更多
关键词 猪繁殖与呼吸障碍综合征 胸膜肺炎放线杆菌 分离鉴定 药敏试验
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Intrinsic fluctuation and susceptibility in somatic cell reprogramming process
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作者 Jian Shen xiaomin zhang +3 位作者 Qiliang Li Xinyu Wang Yunjie Zhao Ya Jia 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第4期113-120,共8页
Based on the coherent feedforward transcription regulation loops in somatic cell reprogramming process, a stochastic kinetic model is proposed to study the intrinsic fluctuations in the somatic cell reprogramming. The... Based on the coherent feedforward transcription regulation loops in somatic cell reprogramming process, a stochastic kinetic model is proposed to study the intrinsic fluctuations in the somatic cell reprogramming. The Fano factor formulas of key genes expression level in the coherent feedforward transcription regulation loops are derived by using of Langevin theory. It is found that the internal fluctuations of gene expression levels mainly depend on itself activation ratio and degradation ratio. When the self-activation ratio(or self-degradation ratio) is increased, the Fano factor increases reaches a maximum and then decreases. The susceptibility is used to measure the sensitivity of steady-state response to the variation in systemic parameters. It is found that with the increase of the self-activation ratio(or self-degradation ratio), the susceptibility of steady-state increases at first, it reaches a maximum, and it then decreases. The magnitude of the maximum is increased with the increase of activated ratio by the upstream transcription factor. 展开更多
关键词 INTRINSIC FLUCTUATION SUSCEPTIBILITY coherent feedforward LOOPS SOMATIC cell REPROGRAMMING
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Efficient conversion of H_(2)S into mercaptan alcohol by tertiary-amine functionalized ionic liquids
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作者 Wenjie Xiong Mingzhen Shi +4 位作者 Yan Lu xiaomin zhang Xingbang Hu Zhuoheng Tu Youting Wu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2022年第10期197-204,共8页
The resource utilization of hydrogen sulfide(H_(2)S)is of great significance in natural gas chemical industry.Described herein have developed a novel method mediated in tertiary amine-functionalized ionic liquids(ILs)... The resource utilization of hydrogen sulfide(H_(2)S)is of great significance in natural gas chemical industry.Described herein have developed a novel method mediated in tertiary amine-functionalized ionic liquids(ILs)to convert H_(2)S into mercaptan alcohols with enols.The effect of ILs,substra te scope,and regeneration experiments have been investigated.It is found that the conversion of 3-methyl-2-buten-1-ol by H_(2)S can reach 52%with a 50%(mol)catalyst loading of bis(2-dimethylaminoethyl)ether methoxyacetate within 12 hat 90℃.The reaction mechanism was speculated based on theoretical calculation.Besides,a plausible reaction-separation-integrated strategy was further proposed.This work reveals an effective insight into the capture and catalytic conversion of H_(2)S to high valuable mercaptan alcohol,which makes the utilization method of H_(2)S resource universal and has the potentiality for industrial application. 展开更多
关键词 Ionic liquids Reaction CATALYSIS Hydrogen sulfide DFT calculation
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