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The effect of NiO-Ni_(3)N interfaces in in-situ formed heterostructure ultrafine nanoparticles on enhanced polysulfide regulation in lithium-sulfur batteries

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Journal of Energy Chemistry 2022年第5期31卷 762-770页

作者： Jun Pu Zhenghua Wang Pan Xue Kaiping Zhu jiachen Li Yagang Yao Key Laboratory of Functional Molecular Solids Ministry of EducationAnhui Provincial Engineering Laboratory for New-Energy Vehicle Battery Energy-Storage MaterialsCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu 241002AnhuiChina National Laboratory of Solid State Microstructures College of Engineering and Applied SciencesJiangsu Key Laboratory of Artificial Functional MaterialsCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093JiangsuChina School of Chemical Engineering Northwest UniversityXi’an 710069ShaanxiChina Division of Nanomaterials and Jiangxi Key Lab of Carbonene Materials Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesNanchang 330200JiangxiChina

Inhibiting the “shuttle effect” of soluble polysulfides and improving reaction kinetics are the key factors necessary for further exploration of high-performance Li-S batteries. Herein, an effective interface engineering strategy is reported, wherein nitriding of an Ni-based precursor is controlled to enhance Li-S cell regulation. The resulting in-situ formed NiO-Ni_(3)N heterostructure interface not only has a stronger polysulfide adsorption effect than that of monomeric NiO or Ni_(3)N but also has a faster Li ion diffusion ability than a simple physical mixture. More importantly, this approach couples the respective advantages of NiO and Ni_(3)N to reduce polarization and facilitate electron transfer during polysulfide reactions and synergistically catalyze polysulfide conversion. In addition, ultrafine nanoparticles are thought to effectively improve the use of additive materials. In summary, Li-S batteries based on this NiO-Ni_(3)N heterostructure have the features of long cycle stability, rapid charging-discharging, and good performance under high sulfur loading.

关键词： NiO-Ni_(3)N heterostructure Interface effect Ultrafine nanoparticles Li-S batteries Polysulfides

青藏高原城市洪涝缓解能力评估——以拉萨市为例

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北京师范大学学报（自然科学版） 2022年第2期58卷 318-327页

作者：戴开璇沈石程昌秀耿佳辰张天媛北京师范大学地表过程与资源生态国家重点实验室环境演变与自然灾害教育部重点实验室地理科学学部地理数据与应用分析中心北京100875 国家青藏高原科学数据中心北京100101

通过耦合FUTURES城市扩张模拟模型和城市洪涝缓解能力评估模型,综合不同气候变化和城市扩张情景对拉萨市洪涝缓解能力的历史及未来变化进行了定量评估.结果发现:1)2000-2015年,拉萨市各区洪涝缓解能力平均降低了5.34%.其中城关区和堆龙... 详细信息

通过耦合FUTURES城市扩张模拟模型和城市洪涝缓解能力评估模型,综合不同气候变化和城市扩张情景对拉萨市洪涝缓解能力的历史及未来变化进行了定量评估.结果发现:1)2000-2015年,拉萨市各区洪涝缓解能力平均降低了5.34%.其中城关区和堆龙德庆区分别降低了4.63%和8.55%,仅达孜区的缓解能力提高了1.13%.2)城关区未来洪涝缓解能力在RCP4.5和RCP8.5情景下分别平均降低了15.01%和29.52%,堆龙德庆区则分别降低了16.16%和31.95%.3)城关区和堆龙德庆区的新增城镇用地造成其缓解能力比原自然地表降低50%以上,在城市扩张中采取保护水体措施,能够有效减少缓解能力的退化.4)未来城市扩张造成拉萨市未来洪涝缓解能力的大幅降低,而气候变化进一步扩大了其退化程度.因此,拉萨市在未来应该遏制城市建设向水体、草地扩张的趋势,提高城市土地利用效率.并且应当加强城市内部绿色基础设施的建设,适度提高防洪排水设施标准,以应对气候变化可能造成的极端降水事件.

关键词：极端降水城市洪涝城市扩张 FUTURES模型 InVEST-UFRM模型

Manipulation of IME4 expression, a global regulation strategy for metabolic engineering in Saccharomyces cerevisiae

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药学学报:英文版 2023年第6期13卷 2795-2806页

作者： Jianxun Zhu Tianyue An Wenlong Zha Ke Gao Ting Li jiachen Zi State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugsand NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China College of Pharmacy Jinan UniversityGuangzhou 510632China

Metabolic engineering has been widely used for production of natural medicinal molecules.However, engineering high-yield platforms is hindered in large part by limited knowledge of complex regulatory machinery of metabolic network. N~6-Methyladenosine(m^(6)A) modification of RNA plays critical roles in regulation of gene expression. Herein, we identify 1470 putatively m^(6)A peaks within 1151 genes from the haploid Saccharomyces cerevisiae strain. Among them, the transcript levels of 94 genes falling into the pathways which are frequently optimized for chemical production, are remarkably altered upon overexpression of IME4(the yeast m^(6)A methyltransferase). In particular, IME4 overexpression elevates the mRNA levels of the methylated genes in the glycolysis, acetyl-CoA synthesis and shikimate/aromatic amino acid synthesis modules. Furthermore, ACS1 and ADH2, two key genes responsible for acetyl-CoA synthesis, are induced by IME4 overexpression in a transcription factor-mediated manner.Finally, we show IME4 overexpression can significantly increase the titers of isoprenoids and aromatic compounds. Manipulation of m^(6)A therefore adds a new layer of metabolic regulatory machinery and may be broadly used in bioproduction of various medicinal molecules of terpenoid and phenol classes.

关键词： RNA m^(6)A modification Metabolic engineering Saccharomyces cerevisiae Isoprenoids Aromatic compounds

An Improved Biogeography-Based Optimization Algorithm for Blocking Flow Shop Scheduling Problem

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Chinese Journal of Electronics 2018年第2期27卷 351-358页

作者： LIU Shufen WANG Pengfei ZHANG jiachen College of Computer Science and Technology Jilin University

To solve the blocking flow shop scheduling with maximum completion time(i.e. makespan) criterion,we proposed an Improved biogeography-based optimization algorithm(IBBO). The framework of basic BBO algorithm is used in the IBBO algorithm, and the introduction of the NEH algorithm make IBBO algorithm with certain quality and diversity. The migration operation based on the insert rules and the mutation operation based on swap rules are presented to avoid the occurrence of illegal solution of the blocking flow shop problem. An insertneighborhood search algorithm was used to strengthen the local search ability of the IBBO. The computational results show the effectiveness of the proposed IBBO algorithm in solving the blocking flow shop scheduling with maximum completion time criterion.

关键词： Blocking flow shop Biogeography-based optimization Makespan Insert-neighborhood search algorithm

Decision-making models on perceptual uncertainty with distributional reinforcement learning

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Green Energy and Intelligent Transportation 2023年第2期2卷 29-39页

作者： Shuyuan Xu Qiao Liu Yuhui Hu Mengtian Xu jiachen Hao School of Mechanical Engineering Beijing Institute of Technology100081 BeijingChina Beili Huidong(Changshu)Vehicle Technology Company 215513 SuzhouChina

Decision-making for autonomous vehicles in the presence of obstacle occlusions is difficult because the lack of accurate information affects the judgment.Existing methods may lead to overly conservative strategies and timeconsuming computations that cannot be balanced with efficiency.We propose to use distributional reinforcement learning to hedge the risk of strategies,optimize the worse cases,and improve the efficiency of the algorithm so that the agent learns better actions.A batch of smaller values is used to replace the average value to optimize the worse case,and combined with frame stacking,we call it Efficient-Fully parameterized Quantile Function(EFQF).This model is used to evaluate signal-free intersection crossing scenarios and makes more efficient moves and reduces the collision rate compared to conventional reinforcement learning algorithms in the presence of perceived occlusion.The model also has robustness in the case of data loss compared to the method with embedded long and short term memory.

关键词： Autonomous vehicles Reinforcement learning Sensing occlusion Partially observable markov decision process Unsiganlized intersections

Characteristics and applications of gas desorption with excavation disturbances in coal mining

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International Journal of Coal Science & Technology 2015年第1期2卷 30-37页

作者： jiachen Wang College of Resources and Safety Engineering China University of Mining & Technology (Beijing) Beijing 100083 China State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology (Beijing) Beijing 100083 China

According to the deficiency of experiment system for gas adsorption and desorption in coal mass, a large scale experiment system is developed independently by researchers. This experiment system is composed of primary and auxiliary boxes, power transmission system, mining system, loading system, gas charging system, data monitoring and intelligent acquisition system. The maximum experiment coal consumption is 1200 kg, the mining system is developed to conduct experiment for gas desorption under excavating disturbance, and the plane-charging cribriform ventilation device is developed to realize uniform ventilation for experiment coal sample, which is accord with the actual gas source situation of coal bed. The desorption characteristics of gas in coal are experimentally studied under the conditions of nature and mining using the experiment system. The results show that, compare with nature condition, the permeability of coal and the velocity of gas desorption could significantly increase under the influence of coal pressure relief and destruction caused by mining, and the degree of gas desorption could somewhat increase too. Finally, pressure relief gas extraction of current seam and adjacent seams after mining in a certain coal mine of Yangquan mining area are introduced, and the gas desorption experiment results is verified by analyzing the effect of gas extraction.

关键词：瓦斯解吸解吸特征开挖扰动煤开采实验系统应用动力传动系统试验系统

Functional mechanism on stem cells by tea(Camellia sinensis)bioactive compounds

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Food Science and Human Wellness 2022年第3期11卷 579-586页

作者： Yao Cheng jiachen Sun Hui Zhao Hongxing Guo Jianying Li School of Biotechnology and Food Science Tianjin University of CommerceTianjin 300134China The Third Central Clinical College Tianjin Medical UniversityTianjin 300170China

Camellia sinensis(tea),one of the most popular commercial crops,is commonly applied in all parts of the world.The main active ingredients of tea include polyphenols,alkaloids,polysaccharides,amino acids,aroma and volatile constitutes,all of which are potentially responsible for the activities of tea.Stem cells(SCs)are the immature and undifferentiated cells by a varying capacity for proliferation,self-renewal and the capability to differentiate into one or more different derivatives with specialized function or maintain their stem cell phenotype.Herein,a thorough review is conducted of the functional mechanism on SCs by tea bioactive compounds.

关键词： Functional mechanism Stem cell Camellia sinensis Bioactive compounds

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高温压力管道过热探测与试验研究

南京航空航天大学学报 2014年第4期46卷 618-624页

作者：潘家辰蒋彦龙施红王合旭南京航空航天大学航空宇航学院南京210016

在分析现有民用飞机空气导管过热探测系统工作原理的基础上,指出飞机空气导管过热探测系统的不足。基于热敏材料特性和组合电路,设计了一种高温压力管道过热探测系统及方法,实现了对高温压力管路的过热报警并定位的功能,并提出了相应的... 详细信息

在分析现有民用飞机空气导管过热探测系统工作原理的基础上,指出飞机空气导管过热探测系统的不足。基于热敏材料特性和组合电路,设计了一种高温压力管道过热探测系统及方法,实现了对高温压力管路的过热报警并定位的功能,并提出了相应的优化方案。通过搭建管道过热探测试验台,对设计的方案进行了试验验证,并考察过热段长度及管内气体温度对探测系统响应时间的影响。研究结果表明:探测系统的响应时间随着管道内气体的温度升高而减少,但当管内温度达到一定值时,响应时间几乎保持不变。同时,探测系统的响应时间随着过热段的长度增加而减少。

关键词：高温压力管道过热探测定位

Design of Power Amplifier for mm Wave 5G and Beyond

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第4期36卷 579-588页

作者： LI Lianming SI jiachen CHEN Linhui School of Information Science and Engineering Southeast UniversityNanjing 210096P.R.China National Mobile Communications Research Laboratory Nanjing 210096P.R.China Purple Mountain Laboratories Nanjing 211100P.R.China

With targets of cost reduction per bit and high energy efficiency,5G and beyond call for innovation in the mmWave transmitter architecture and the power amplifier(PA)circuit.To illustrate these points,this paper firstly explains the benefits and design implications of the hybrid beamforming structure in terms of the mmWave spectrum characteristics,energy efficiency,data rate,communication capacity,coverage and implementation technology choices.Then after reviewing the techniques to improve the power amplifier(PA)output power and efficiency,the design considerations and test results of 60 GHz and 90 GHz mmWave PAs in bulk complementary metal oxide semiconductor(CMOS)process are shown.

关键词： 5G and beyond 6G beamforming complementary metal oxide semiconductor(CMOS) mmWave multiple⁃input multiple⁃output(MIMO) power amplifier transmitter