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Neural Regeneration Research 2024年第3期19卷 563-570页

作者： Bo Han Weishi Liang yong Hai Duan Sun Hongtao ding Yihan Yang Peng Yin Department of Orthopedics Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

Distraction spinal cord injury is caused by some degree of distraction or longitudinal tension on the spinal cord and commonly occurs in patients who undergo corrective operation for severe spinal *** the increased degree and duration of distraction,spinal cord injuries become more serious in terms of their neurophysiology,histology,and *** few studies have been published on the specific characteristics of distraction spinal cord *** this study,we systematically review 22 related studies involving animal models of distraction spinal cord injury,focusing particularly on the neurophysiological,histological,and behavioral characteristics of this *** addition,we summarize the mechanisms underlying primary and secondary injuries caused by distraction spinal cord injury and clarify the effects of different degrees and durations of distraction on the primary injuries associated with spinal cord *** provide new concepts for the establishment of a model of distraction spinal cord injury and related basic research,and provide reference guidelines for the clinical diagnosis and treatment of this disease.

关键词： animal models behavior distraction heterogeneity histology mechanism neurophysiology spinal cord injury systematic review tension

Chemical Synthesis of a Key Precursor Relevant to the Tetrasaccharide Repeating Unit from Treponema medium ATCC 700293

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Chinese Journal of Chemistry 2024年第14期42卷 1615-1622页

作者： Wenbin Sun Guangzong Tian Meiru ding Chunjun Qin Xiaopeng Zou Jing Hu jian Yin Key Laboratory of Carbohydrate Chemistry and Biotechnology Ministry of EducationSchool of Biotechnology&School of Life Sciences and Health EngineeringJiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China Wuxi School of Medicine Jiangnan UniversityLihu Avenue 1800WuxiJiangsu214122 China

Treponema is a Gram-negative anaerobic bacterium,among which the pathogenic Treponema can cause various diseases,such as venereal syphilis(Treponema pallidum),yaws(Treponema carateum),and oral diseases(Treponema denticola and Treponema medium).Although different from conventional lipopolysaccharides,the extracellular glycoconjugate of Treponema may still be a potential antigen and provide a candidate for vaccine ***,we completed the first chemical synthesis of Treponema medium ATCC 700293 tetrasaccharide precursor containing L-ornithine(L-Orn)and D-aspartic acid(D-Asp)*** efficiency of non-reducing end disaccharide formation has been improved by optimizing the assembly of the protecting groups in the donors and ***[3+1]glycosylation strategy attempted to reduce the length of the acceptor to increase the nucleophilicity of the hydroxyl group,thereby improving the efficiency of synthesizing the target *** L-Orn derivative was introduced at the final stage due to its influence on the glycosylation stereospecificity and ***,the successful introduction of two amino acid derivatives and the synthesis of a tetrasaccharide precursor with complex functional-group modifications have provided valuable insights for synthesizing other complex bacterial glycans.

关键词： Glycosylation Total synthesis Treponema medium ATCC 700293 Tetrasaccharide precursor Protecting group Oligosaccharides Regioselectivity Neighboring-group effects

Strongly Coupled Ag/Sn-SnO_(2)Nanosheets Toward CO_(2)Electroreduction to Pure HCOOH Solutions at Ampere‑Level Current

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Nano-Micro Letters 2024年第3期16卷 212-226页

作者： Min Zhang Aihui Cao Yucui Xiang Chaogang Ban Guang Han Junjie ding Li‑yong Gan Xiaoyuan Zhou College of Physics and Center of Quantum Materials and Devices Chongqing UniversityChongqing 401331People’s Republic of China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences(CAS)Fuzhou 350002People’s Republic of China College of Materials Science and Engineering Chongqing UniversityChongqing 400044People’s Republic of China Institute of New Energy Storage Materials and Equipment Chongqing 401135People’s Republic of China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400044People’s Republic of China

Electrocatalytic reduction of CO_(2) converts intermittent renewable electricity into value-added liquid products with an enticing prospect,but its practical application is hampered due to the lack of high-performance ***,we elaborately design and develop strongly coupled nanosheets composed of Ag nanoparticles and Sn-SnO_(2) grains,designated as Ag/Sn-SnO_(2) nanosheets(NSs),which possess optimized electronic structure,high electrical conductivity,and more accessible *** a result,such a catalyst exhibits unprecedented catalytic performance toward CO_(2)-to-formate conversion with near-unity faradaic efficiency(≥90%),ultrahigh partial current density(2,000 mA cm^(−2)),and superior long-term stability(200 mA cm^(−2),200 h),surpassing the reported catalysts of CO_(2) electroreduction to ***,in situ attenuated total reflection-infrared spectra combined with theoretical calculations revealed that electron-enriched Sn sites on Ag/Sn-SnO_(2)NSs not only promote the formation of*OCHO and alleviate the energy barriers of*OCHO to*HCOOH,but also impede the desorption of H*.Notably,the Ag/Sn-SnO_(2)NSs as the cathode in a membrane electrode assembly with porous solid electrolyte layer reactor can continuously produce~0.12 M pure HCOOH solution at 100 mA cm^(−2)over 200 *** work may inspire further development of advanced electrocatalysts and innovative device systems for promoting practical application of producing liquid fuels from CO_(2).

关键词： Electrochemical CO_(2)reduction Coupled Ag/Sn-SnO_(2)nanosheets Electronic structure Porous solid electrolyte Pure

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青藏高原唐古拉山区降水观测误差修正分析

水科学进展 2009年第3期20卷 403-408页

作者：何晓波叶柏生丁永建中国科学院寒区旱区环境与工程研究所中国科学院生态水文与流域科学重点实验室甘肃兰州730000 中国科学院寒区旱区环境与工程研究所冰冻圈科学国家重点实验室甘肃兰州730000

青藏高原由于降水观测点分布等原因一直是水文和气候研究的薄弱环节。2005年5～10月在青藏高原唐古拉山中部冬克玛底河流域进行连续的人工气象观测。观测期间根据不同降水类型和气温之间的相关关系，采用气温2．7℃为临界值对降水类型... 详细信息

青藏高原由于降水观测点分布等原因一直是水文和气候研究的薄弱环节。2005年5～10月在青藏高原唐古拉山中部冬克玛底河流域进行连续的人工气象观测。观测期间根据不同降水类型和气温之间的相关关系，采用气温2．7℃为临界值对降水类型进行了划分，利用已有的T-200B型自动雨雪量计和普通雨量计的修正公式，并在日尺度基础上对降水进行了修正对比。经过修正，中游T-200B型雨量站全年降水量662．1mm；普通雨量计全年降水量为657．2mm；2005年修正后的降水量相比1993年观测到的降水量472mm增加了近200mm。结果表明在高寒山区降水观测，依据同步观测的气温划分降水类型，可以根据相关修正公式修正T-200B型自动雨雪量计和普通雨量计降水观测值。从而能够在高寒山区恶劣的自然环境自动连续准确的观测高寒区域的降水。

关键词：青藏高原唐古拉山降水观测误差修正降水类型

A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

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Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan He Weidong Wang Zhi ding Wen He yong He Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle ***,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly ***,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating *** remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional *** utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS *** addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical *** work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial ***,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

Regulation of the quantum barrier and carrier transport toward high-efficiency quasi-2D Dion-Jacobson tin perovskite solar cells

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Journal of Energy Chemistry 2024年第8期95卷 200-207,I0005页

作者： Huanhuan Yao Chang Shi Tai Wu Shurong Wang Mingyu Yin Liming ding yong Hua Feng Hao School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China Yunnan Key Laboratory for Micro/Nano Materials&Technology School of Materials and EnergyYunnan UniversityKunming 650091YunnanChina Center for Excellence in Nanoscience(CAS) Key Laboratory of Nanosystem and Hierarchical Fabrication(CAS)National Center for Nanoscience and TechnologyBeijing 100190China

Quasi-2D Dion-Jacobson(DJ)tin halide perovskite has attracted much attention due to its elimination of Van der Waals gap and enhanced environmental ***,the bulky organic spacers usually form a natural quantum well structure,which brings a large quantum barrier and poor film quality,further limiting the carrier transport and device ***,we designed three organic spacers with different chain lengths(ethylenediamine(EDA),1,3-propanediamine(PDA),and 1,4-butanediamine(BDA))to investigate the quantum barrier *** and experimental characterizations indicate that EDA with short chain can reduce the lattice distortion and dielectric confinement effect,which is beneficial to the effective dissociation of excitons and the inhibition of trap-free non-radiative *** addition,EDA cation shows strong interaction with the inorganic octahedron,realizing large aggregates in precursor solution and high-quality films with improved structural ***,femtosecond transient absorption proves that EDA cations can also weaken the formation of small n-phases with large quantum barrier to achieve effective carrier transport between different ***,the quasi-2D DJ(EDA)FA_(9)Sn_(10)I_(31)solar cells achieves a 7.07%power conversion efficiency with good environment ***,this work sheds light on the regulation of the quantum barrier and carrier transport through the chain length of organic spacer for qua si-2D DJ lead-free perovskites.

关键词： Chain lengths Organic spacers Quantum well Carrier transport Lattice distortion

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非对称非均布负荷下配电网线损改进算法

高电压技术 2008年第9期34卷 1987-1991页

作者：丁坚勇陈丹杨东俊武汉大学电气工程学院武汉430072 国家电网公司华中公司武汉430071

配电网络是指二次降压变压器低压侧直接或降压后向用户供电的网络,具有网络复杂,电压低,网损大的特点。三相不对称运行是低压配电网的主要特点,目前低压线损的理论计算问题大多是采用近似等效的简化算法。为方便和较精确地计算线损,针... 详细信息

配电网络是指二次降压变压器低压侧直接或降压后向用户供电的网络,具有网络复杂,电压低,网损大的特点。三相不对称运行是低压配电网的主要特点,目前低压线损的理论计算问题大多是采用近似等效的简化算法。为方便和较精确地计算线损,针对低压配电网络的结构特点和实际运行情况在综合比较分析了各种算法的适用范围和优缺点的基础上提出了一种能计及三相不对称和负荷分布不均匀性的低压配网理论线损改进算法,用C++ Builder编程和算法分析的结果表明:改进新算法结合了各种算法的优点,算法不设置过多的简化假设条件,因而更符合低压配电网实际。

关键词：低压配网负荷分布三相不平衡线损竹节法负荷形状系数

Sequence-Controlled Synthesis of Alternating Poly(ester amide)s using Water as Control Agent in One-Pot

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Chinese Journal of Polymer Science 2024年第8期42卷 1015-1020页

作者： Tao Liu Fang-Fang Niu Kan Cheng Yu-Min Xia Bo-Mou Ma Xue-Li Wang jian-yong Yu yong He State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China

Poly(ester amide)s(PEAs)attract much attention as a new kind of biodegradable ***,the synthesis of PEAs with sequence-regulated chain structures is still complicated due to the multistep polymerization,high monomer purity,as well as the usage of organic solvents,which greatly inhibits its development and ***,a one-pot strategy without solvent was developed to synthesize the alternating PEA fromα,ω-amino alcohol and dicarboxylic acid by sequential polycondensation,where water was used as the controlling agent for amidation and ***,the amidation and esterification were controlled to proceed in turn by adding or removing water,realizing the one-pot preparation of alternating *** resultant PEA is characterized by^1H-and^(13)C-NMR,and its chain structure is confirmed to be highly quasi-alternating similar to alternating PEAs prepared by classical methods The evaluations from DSC and DMA demonstrate that the properties of quasi-alternating PEA(T_(m)=102℃,ΔH_(m)=30J·g^(-1))are far superior to those of random PEA(T_(m)=72℃,ΔH_(m)<1 J·g^(-1)).

关键词： Biodegradable macromolecules Polymer architectures Sequence-controlled synthesis One-pot polymerization

Magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming Ma jian-liang Zhang Yao-zu Wang Xiao-yong Ma Gui-lin Wang Zhuo Li Hui-qing jiang Zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

塔里木河上游阿克苏地区水资源与绿洲农业种植结构调整优化研究——以拜城县为例

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干旱区资源与环境 2007年第5期21卷 29-34页

作者：陈彩苹丁永建刘时银中国科学院寒区旱区环境与工程研究所甘肃兰州730000

水是干旱区绿洲农业发展的生命线,发展节水型农业成为目前干旱区农业发展的当务之急。位于塔里木河上游的阿克苏地区,是新疆重要的绿洲农业区和主要的粮食、棉花和瓜果基地。对目前的农业种植结构进行调整优化,达到节水和增效的目的,具... 详细信息

水是干旱区绿洲农业发展的生命线,发展节水型农业成为目前干旱区农业发展的当务之急。位于塔里木河上游的阿克苏地区,是新疆重要的绿洲农业区和主要的粮食、棉花和瓜果基地。对目前的农业种植结构进行调整优化,达到节水和增效的目的,具有重要的现实意义。本文以拜城县为例,通过构建线性规划数学模型,在水资源约束下,进行了作物种植结构的调整和优化,调整后的种植结构能使有限的水资源发挥最大的经济效益,基本符合新疆绿洲区农业种植结构调整的需要,为制定科学合理的农作物种植结构发展方案提供依据。

关键词：水资源农业种植结构拜城县