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Construction of a Rice Glycosyltransferase Phylogenomic Database and Identification of Rice-Diverged Glycosyltransferases

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Molecular Plant 2008年第5期1卷 858-877页

作者： pei-jian cao Laura E. Bartley Ki-Hong Jung Pamela C. Ronald Department of Plant Pathology University of California Davis CA 95616 and the Joint BioEnergy Institute Emeryville CA 94710 USA Institute of Bioinformatics Zhejiang University Hangzhou Zhejiang 310029 China

Glycosyltransferases （GTs; EC 2.4.x.y） constitute a large group of enzymes that form glycosidic bonds through transfer of sugars from activated donor molecules to acceptor molecules. GTs are critical to the biosynthesis of plant cell walls, among other diverse functions. Based on the Carbohydrate-Active enZymes （CAZy） database and sequence ***, we have identified 609 potential GT genes （loci） corresponding to 769 transcripts （gene models） in rice （Oryza sativa）, the reference monocotyledonous species. Using domain composition and sequence similarity, these rice GTs were classified into 40 CAZy families plus an additional unknown class. We found that two Pfam domains of unknown function, PF04577 and PF04646, are associated with GT families GT61 and GT31, respectively. To facilitate functional analysis of this important and large gene family, we created a phylogenomic Rice GT Database （http：//ricephylogenomics. ***/cellwalls/gtJ）. Through the database, several classes of functional genomic data, including mutant lines and gene expression data, can be displayed for each rice GT in the context of a phylogenetic tree, allowing for comparative analysis both within and between GT families. Comprehensive digital expression analysis of public gene expression data revealed that most （-80%） rice GTs are expressed. Based on analysis with Inparanoid, we identified 282 ‘rice-diverged＇ GTs that lack orthologs in sequenced dicots （Arabidopsis thaliana, Populus tricocarpa, Medicago truncatula, and Ricinus communis）. Combining these analyses, we identified 33 rice-diverged GT genes （45 gene models） that are highly expressed in above-ground, vegetative tissues. From the literature and this analysis, 21 of these loci are excellent targets for functional examination toward understanding and manipulating grass cell wall qualities. Study of the remainder may reveal aspects of hormone and protein metabolism that are critical for rice biology. This list of 33 genes a

关键词： glycosyltransferases GT phylogenetic tree orthologs expression pattern mutant lines phylogenomic database rice cell wall.

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Development of an Experimental EUVL System

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光学精密工程 2001年第5期9卷 418-423页

作者： JIN Chun shui, MA Yue ying, pei Shu,cao jian lin (Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130022, China) 中科院长春光学精密机械与物理所吉林长春 130022

The authors have developed an experimental system for the studies of extreme ultraviolet projection lithography at 13.0nm wavelength, which includes a laser plasma source, an ellipsoidal condenser, a transmission mask and a Schwarzschild optics. The optical system is optimized to achieve 0.1μm resolution over a 0.1mm diameter image field of view and the mirrors of the objective were coated with Mo/Si multilayer to provide 60% reflectance at near normal incidence angle for 13.0nm radiation.

关键词： extreme ultraviolet projection lithography multilayer reflectors Schwarzschild optics

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纳米粒子在骨组织工程化基因修饰治疗中的应用

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中国组织工程研究 2025年第22期29卷 4771-4783页

作者：李光照裴锡波王剑口腔疾病防治全国重点实验室国家口腔医学中心国家口腔疾病临床医学研究中心四川大学华西口腔医院修复科四川省成都市610041

背景:传统的骨组织工程技术治疗临界骨缺损存在成骨效率低、安全性差等问题。而以非病毒纳米粒子为基因载体构建的基因强化型骨组织工程移植物,具有更高的成骨效率和安全性,引起了国内外学者的广泛关注和研究。目的:对当前国内外有关纳... 详细信息

背景:传统的骨组织工程技术治疗临界骨缺损存在成骨效率低、安全性差等问题。而以非病毒纳米粒子为基因载体构建的基因强化型骨组织工程移植物,具有更高的成骨效率和安全性,引起了国内外学者的广泛关注和研究。目的:对当前国内外有关纳米粒子在组织工程成骨基因治疗研究中取得的新技术、新方法以及面临的挑战等进行综述,旨在为纳米粒子介导的骨组织工程基因治疗研究提供参考。方法:第一作者在Pub Med、Web of Science和中国知网数据库上进行文献检索,并以“Bone defect repair,Bone tissue engineering,Gene delivery,Nanoparticles,Non-viral gene vector,Sustained release technology,Sequential release,Targeted delivery”作为英文检索词,以“骨缺损修复,骨组织工程,基因递送,纳米粒子,非病毒基因载体,缓释技术,序贯释放,靶向递送”作为中文检索词,最终纳入84篇文献进行总结。结果与结论:(1)在骨缺损愈合的各个生理阶段进行针对性的基因递送可以显著增强骨修复效果。在早期炎症阶段,通过纳米粒子递送抗炎基因来调节炎症反应,可以为后续骨愈合奠定基础;在血管新生期,向局部递送促血管化基因有助于形成高度组织化、可灌注的血管系统,加快骨愈合速度;随着血管化的进行,骨骼的神经再支配也开始发生,此时递送促神经再生的功能性基因有利于促进神经化骨再生;在成骨阶段,通过构建纳米粒子-成骨基因复合物,可以直接提升支架及体内新骨形成的效率。(2)各种有机、无机纳米颗粒、金属有机框架和外泌体等非病毒纳米载体,在骨组织工程基因治疗中具有巨大的潜力,这些纳米基因载体各有其独特的优势和不足,因此在实际应用时,需要根据基因转染效率、生物安全性和成骨特性等因素选择最合适的类型。(3)为了全面提升递送基因的效果,目前主要通过对纳米载体进行各种功能设计来增强基因转染效率,包括增强缓释性和多基因递送序贯性等时间调控能力、增强对骨组织和成骨相关细胞的空间靶向能力、增强跨膜运输效率和细胞核靶向能力等全过程调控手段。(4)未来要进一步推动纳米粒子介导的骨组织工程基因治疗在临床上的应用,还需要克服诸多技术挑战,包括提高有机纳米基因载体的基因转染效率、降低无机纳米载体的生物安全性风险、优化新型纳米载体的生产工艺以及促进其它生理过程与成骨交互作用等,这些问题也是未来骨组织工程基因治疗的研究热点和潮流。

关键词：骨缺损修复骨组织工程基因递送纳米粒子非病毒基因载体缓释技术序贯释放靶向性递送

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Reduction of 1-3 mm iron ore by H_2 in a fluidized bed

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 620-625页

作者： jian-ming Pang pei-min Guo pei Zhao Chao-zhen cao Ding-guo Zhao Duo-gang Wang The State Key Laboratory for Advanced Steel Processes and Materials Central Iron and Steel Research Institute Beijing 100081 China

The reduction of 1-3 mm fine powder of iron ore by H2 was conducted in a lab-fabricated kg class high temperature fluidized bed. The results show that the differential pressure in the fluidized bed, which has small fluctuation with time, increases with the increase of gas flowing velocity. The utilization ratio of gas decreases when the reaction lasts longer time indicating that the reaction is faster at the beginning of reduction and becomes slower in the latter process. The higher the reaction temperature is, the higher the utilization ratio of gas is, but the difference of utilization ratio among the different temperatures becomes smaller with time. The utilization ratio of gas and the metallization ratio can reach 9% and 84% respectively at 750℃ for 20 min, which shows the reduction reaction by H2 is very fast. The increase of metallization ratio with gas velocity performs quite good linearity, which shows that a higher velocity of reducing gas can be used to improve the productivity of the reactor when H2 is used as reducing gas. With the increase of charge height, the metallization ratio decreases, but the utilization ratio of gas increases. The reaction temperature can be reduced to 700-750℃ from 800-850℃ when H2 is used as reducing gas.

关键词： hydrogen fluidized bed fine powder iron ore ironmaking reduction reaction

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Multi-level Aggregation of Conjugated Polymers in Solution:Advances and Challenges

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Chinese Journal of Polymer Science 2023年第10期41卷 1498-1500页

作者： jian pei Beijing National Laboratory for Molecular Sciences(BNLMS) Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenter of Soft Matter Science and EngineeringCollege of Chemistry and Molecular EngineeringPeking UniversityBeijingChina

Since the discovery of conductive polyacetylene,conjugated polymers have attracted considerable attention in the past decades for their applications in optoelectronic devices,such as organic field-effect transistors(OFETs),light-emitting diodes(OLEDs),and photovoltaics(OPVs).The intrinsic mechanical flexibility of conjugated polymers endows them as promising candidates for flexible and wearable *** iterative molecular design refinement and processing technique optimization,significant improvements in device performance have been *** mobility has reached over 10 cm^(2)·V^(−1)·s^(−1),exceeding the benchmark of 1 cm^(2)·V^(−1)·s^(−1)set by their amorphous silicon *** conductivity of N-type polymer,poly(benzodifurandione)(PBFDO),exhibited a breakthrough over 2000 S·cm−1,making it an ideal conductor with excellent stability and *** power conversion efficiency(PCE)of conjugated polymer-based solar cells hits 19%,comparable to the commercial polycrystalline silicon solar cells with 14%−19%***,conjugated polymers also show extinguished and promising performance in energy storage and biomedical applications.

关键词： optoelectronic breakthrough exceeding

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Influence of Size of Hematite Powder on Its Reduction Kinetics by H_2 at Low Temperature

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Journal of Iron and Steel Research International 2009年第5期16卷 7-11页

作者： PANG jian-ming GUO pei-min ZHAO pei cao Chao-zhen ZHANG Dian-wei The State Key Laboratory for Advanced Iron and Steel Processes and Materials Central Iron and Steel Research Institute Beijing 100081 China

The reduction kinetics and mechanisms of hematite ore with various particle sizes with hydrogen at low temperature were studied using the thermogravimetric analysis. At the same temperature, after the particle size of powder decreases from 107. 5μm to 2. 0 μm, the surface area of the powder and the contact area between the powder and gas increase, which makes the reduction process of hematite accelerate by about 8 times, and the apparent activation energy of the reduction reaction drops to 36.9 kJ/mol from 78. 3 kJ/mol because the activity of ore powder is improved by refining gradually. With the same reaction rate, the reaction temperature of 6.5 μm powder decreases by about 80 ℃ compared with that of 107. 5 μm powder. Thinner diffusion layer can also accelerate the reaction owing to powder refining. The higher the temperature, the greater is the peak of the reduction rate; at the same temperature, the greater the particle size, the smaller is the peak value of the reduction rate; both inner diffusion and interface chemical reaction play an important role in the whole reaction process.

关键词： iron oxide low temperature reduction kinetics thermogravimetric analysis (TGA), reduction mechanism

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碳排放权交易制度的权利逻辑与规范进路

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河北大学学报（哲学社会科学版） 2025年第1期50卷 123-134页

作者：柯坚曹辰武汉大学环境法研究所湖北武汉430072

当下我国碳排放权交易制度体系正在经历着由政策引领向法治构建的转变。目前碳排放权交易制度行政立法中简单将“权利”与“配额”等同的做法,既无法体现碳排放权所兼具的公法、私法双重特征,也难以有效回应碳排放权交易市场的发展需求... 详细信息

当下我国碳排放权交易制度体系正在经历着由政策引领向法治构建的转变。目前碳排放权交易制度行政立法中简单将“权利”与“配额”等同的做法,既无法体现碳排放权所兼具的公法、私法双重特征,也难以有效回应碳排放权交易市场的发展需求以及完善碳排放权交易制度的规范构建。为此,需要构建以碳排放权交易市场为语境、以碳排放“权利”为逻辑主线的碳排放权交易制度,夯实其法治基础并明确其规范进路。从语境与语义出发,“碳排放权”的表述本身就意味着其私法的权利属性。在碳排放权交易制度的理论逻辑层面,双阶理论可以为碳排放权交易制度中“配额”到“权利”的过渡提供理论支撑;在其实践逻辑层面,碳排放权交易制度需要借助“权利”的确立为其交易市场的展开提供法治的基础。最后,考虑到碳排放权权利属性共识不足、碳排放权交易制度结构尚待稳定、权利基础呈现多元特征以及权利来源并非稳固不变等因素,策略上可以考虑暂时搁置碳排放权权属争议,以权益为抓手、以“权益表现—适用规范领域—法律保护方式”为主线,分步骤、分阶段推进碳排放权交易制度的规范构建。

关键词：碳排放权权益配额权利逻辑规范进路

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Simulation and Optimization of Miniature Ring-Endcap Ion Traps

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Chinese Physics Letters 2014年第4期31卷 46-49页

作者： cao jian State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 Key Laboratory of Atomic Frequency Standards Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 Graduate University of Chinese Academy of Sciences Beijing 100080

With the decrease in dimension of ion traps employed in optical frequency standards and precision spectroscopy, the sensitivity of trapping behavior to trap geometry is more and more prominent. We present a guide for the design and construction of a miniature trap for a single ion confinement, and propose an optimized combination of Tring/Tendcap ≈0.5 and z0≈ ro within the range of To = 0.7 ± 0.2 mm. Compared with the trap used by Huang et al. [Phys. Rev. A 84 （2011）053841], the design can lead to an increase in trap pseudo-potentiM of more than 20% and a reduction on potential anharmonicity of more than 90%. The improvements make the trap closer to an ideal hyperboloidal trap to confine a single ion tightly with the benefit of weaker micro-motion. Considering the imperfection of electrodes machining and traps Mignment, we also demonstrate the importance of trap symmetry, especially on two endcap electrodes.

关键词： Traps Simulation decrease

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Neural-Network-Based Nonlinear Model Predictive Tracking Control of a Pneumatic Muscle Actuator-Driven Exoskeleton

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IEEE/CAA Journal of Automatica Sinica 2020年第6期7卷 1478-1488页

作者： Yu cao jian Huang IEEE Key Laboratory of Image Processing and Intelligent Control School of Artificial Intelligence and AutomationHuazhong University of Science and TechnologyWuhan 430074China

Pneumatic muscle actuators(PMAs)are compliant and suitable for robotic devices that have been shown to be effective in assisting patients with neurologic injuries,such as strokes,spinal cord injuries,etc.,to accomplish rehabilitation ***,because PMAs have nonlinearities,hysteresis,and uncertainties,etc.,complex mechanisms are rarely involved in the study of PMA-driven robotic *** this paper,we use nonlinear model predictive control(NMPC)and an extension of the echo state network called an echo state Gaussian process(ESGP)to design a tracking controller for a PMA-driven lower limb *** dynamics of the system include the PMA actuation and mechanism of the leg orthoses;thus,the system is represented by two nonlinear uncertain *** facilitate the design of the controller,joint angles of leg orthoses are forecasted based on the universal approximation ability of the ESGP.A gradient descent algorithm is employed to solve the optimization problem and generate the control *** stability of the closed-loop system is guaranteed when the ESGP is capable of approximating system *** and experiments are conducted to verify the approximation ability of the ESGP and achieve gait pattern training with four healthy subjects.

关键词： Echo state Gaussian process model predictive control neural network pneumatic muscle actuators-driven exoskeleton

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酚醛基活性炭纤维的研究进展

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合成纤维工业 2017年第5期40卷 62-67页

作者：任东雪焦明立郑瑾刁泉张彩云裴海燕曹健中原工学院材料与化工学院河南郑州450000 中原工学院纺织学院河南郑州450000

从酚醛树脂的合成经纺丝成纤制得酚醛纤维,再将酚醛纤维经碳化、活化最终制得酚醛基活性炭纤维(PACF)的工艺过程综述了PACF的研究进展;其中重点介绍了酚醛树脂的成纤方法:熔融纺丝法、离心纺丝法、湿法纺丝法以及酚醛纤维的化学活化法... 详细信息

从酚醛树脂的合成经纺丝成纤制得酚醛纤维,再将酚醛纤维经碳化、活化最终制得酚醛基活性炭纤维(PACF)的工艺过程综述了PACF的研究进展;其中重点介绍了酚醛树脂的成纤方法:熔融纺丝法、离心纺丝法、湿法纺丝法以及酚醛纤维的化学活化法和物理活化法;阐述了PACF的结构性能以及在吸附领域、超级电容器、高效集热材料,抗菌纤维等方面的应用;展望了PACF的发展前景,指出降低生产成本,避开溶液固化过程、降低污染、拓展应用范围是PACF在未来一段时期内的研究方向。

关键词：酚醛纤维活性炭纤维碳化活化工艺应用进展

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