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Efficient hydrogenolysis of fructose to 1,2.propanediol over bifunctional Ru-WO_(x)-MgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds

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Journal of Energy Chemistry 2024年第5期92卷 311-321页

作者： Shuang Luo Tie Shu Min Mao Haijie Yu Yuxin zheng Daqian ding Lingmei Liu Kexin Yao Jianjian Wang school of Chemistry and Chemical Engineering State Key Laboratory of Coal Mine Disaster Dynamics and ControlInstitute of Advanced Interdisciplinary StudiesMulti-scale Porous Materials CenterChongqing UniversityChongqing 401331China Key Laboratory for Efficient Conversion and Circular Economy of Coal Chemical Engineering CollegeInner Mongolia University of TechnologyHohhot 010051Inner MongoliaChina

Selective conversion of fructose to 1,2.propanediol(1,2.PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction ***,we have successfully synthesized a novel bifunctional Ru-WO_(x)-MgO_(y) catalyst through a facile'one-pot'solvothermal ***,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2.PDO under mild reaction *** yield of 1,2.PDO is up to 56.2.at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2.MPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-MgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2.PDO.

关键词： Biomass Fructose 1,2.Propanediol Retroaldol condensation Heterogenous catalysis

Analyzing the surface passivity effect of germanium oxynitride:a comprehensive approach through first principles simulation and interface state density

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Nuclear science and Techniques 2024年第5期35卷 74-84页

作者： Sheng-Jie du Xiu-Xia Li Yang Tian Yuan-Yuan Liu Ke Jia Zhong-zheng Tang Jian-Ping Cheng Zhi Deng Yu-Lan Li zheng-Cao Li Sha-Sha Lv College of Nuclear science and technology Joint Laboratory of Jinping Ultra‑Low Radiation Background Measurement of Ministry of Ecology and Environment Key Laboratory of Beam technology of Ministry of E{3.cation Beijing Normal UniversityBeijing Normal UniversityBeijing 100875China Joint Research Center Nuctech Company LimitedBeijing 100084China Department of Engineering Physics Key Laboratory of Particle&Radiation Imaging of Ministry of EducationTsinghua UniversityBeijing 100084China Key Laboratory of Advanced materials(MOE) School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

High-purity germanium(HPGe)detectors,which are used for direct dark matter detection,have the advantages of a low threshold and excellent energy *** surface passivation of HPGe has become crucial for achieving an extremely low energy *** this study,first-principles simulations,passivation film preparation,and metal oxide semiconductor(MOS)capacitor characterization were combined to study surface *** calculations of the energy band structure of the -H,-OH,and -NH_(2. passivation groups on the surface of Ge were performed,and the interface state density and potential with five different passivation groups with N/O atomic ratios were accurately analyzed to obtain a stable surface *** on the theoretical calculation results,the surface passivation layers of the Ge_(2.ON_(2. film were prepared via magnetron sputtering in accordance with the optimum atomic ratio *** microstructure,C-V,and I-V electrical properties of the layers,and the passivation effect of the Al/Ge_(2.ON_(2./Ge MOS were characterized to test the interface state *** mean interface state density obtained by the Terman method was 8.4×10^(11) cm^(-2. eV^(-1).The processing of germanium oxynitrogen passivation films is expected to be used in direct dark matter detection of the HPGe detector surface passivation technology to reduce the detector leakage currents.

关键词： Surface passivation High purity germanium detector Germanium nitrogen oxide Interface state density

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预氧化在SiC基陶瓷材料烧结中的作用

天津大学学报（自然科学与工程技术版） 2003年第6期36卷 769-772页

作者：朱玉梅靳正国天津大学电子信息工程学院天津300072 天津大学材料科学与工程学院天津300072

对添加Y2.3.Al2.3.结助剂的SiC材料进行了不同的烧成工艺试验,结果表明,在烧成前先进行预氧化处理的SiC材料,其表面氧化生成的SiO2.进了低温液相的形成,有助于降低该材料的气孔率.同时发现,合适的预氧化温度和保温时间能更有效地降低... 详细信息

对添加Y2.3.Al2.3.结助剂的SiC材料进行了不同的烧成工艺试验,结果表明,在烧成前先进行预氧化处理的SiC材料,其表面氧化生成的SiO2.进了低温液相的形成,有助于降低该材料的气孔率.同时发现,合适的预氧化温度和保温时间能更有效地降低烧结体气孔率,促进烧结.

关键词：预氧化陶瓷材料烧结碳化硅

Key points on temperature change of the past 2.00 years in china

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Progress in Natural science:materials International 2004年第8期 82-89页

作者： GE Quansheng 1, zheng Jingyun 1*, MAN Zhimin 2. FANG Xiuqi 3.1 and ZHANG Piyuan 1(1. Institute of Geographic {2.s and Natural Resources Research, Chinese Academy of {2.s,{3. 100101, china 2. Institute of Chinese History Geography, Fudan university, Shanghai 2.043., china 3. school of Geography,{3. Normal university,{3. 100875, china) Institute of Geographic sciences and Natural Resources Research，Chinese Academy of sciences，{2. 100101，{3. Institute of Chinese History Geography，Fudan university，Shanghai 2.043.，{2. school of Geography，beijing Normal {2.，beijing 100875，china Institute of Geographic sciences and Natural Resources Research，Chinese Academy of sciences，{2. 100101，{3.

Temperature change of the past 2.00 years in china is discussed based on the winter half-year temperature series of the past 2.00 years in eastern china reconstructed recently, and other related studies. The main conclusions are as follows: (1) The Little Ice Age (LIA) in china began in the early of the 14th century (13.0s) and ended in the beginning of the 2.th century (1910s), which was composed of four evident cold stages and three short warming stages. The cold period in the Wei, Jin and South-North dynasties (2.0s～560s) was the only one comparable with LIA for the past 2.00 years. (2. The Medieval Warm Period (MWP) in china began in the 93.s and ended in the 13.0s, which was composed of two warm stages over 100 years and a cold stage less than 100 years. (3. The climate in the Sui and Tang dynasties should be divided into two stages: the climate in the 570s～770s was as warm as that in the 2.th century; while the temperature in the 780s～92.s was lower than that in the 1950s～1970s. (4) In eastern china as a whole, winter half-year temperature variation with over 1 ℃ occurred between the cold and warm stages on centennial scale, while the changing rate exceeded 1.0 ℃ per century. (5) There exists an about 13.0-year periodicity in the historical temperature change. Inferred from the periodicity, the most likely historical analogue for the warming in the 2.th century is the warm stage of the Sui and Tang dynasties (570s～770s), instead of the Medieval Warm Period. (6) Although it was critically warm, the temperature of the 2.th century in eastern china is still within the threshold of the variability of the last 2.00 years.

关键词： eastern china past 2.00 years temperature change.

Rapid and stable calcium-looping solar thermochemical energy storage via co-doping binary sulfate and Al±Mn±Fe oxides

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Green Energy & Environment 2024年第8期9卷 1290-1305页

作者： Changjian Yuan Xianglei Liu Xinrui Wang Chao Song Hangbin zheng Cheng Tian Ke Gao Nan Sun Zhixing Jiang Yimin Xuan Yulong {2. school of Energy and Power Engineering Nanjing University of Aeronautics and Astronautics Key Laboratory of Thermal Management and Energy Utilization of Aviation Vehicles Ministry of Industry and Information Technology Birmingham Centre for Energy Storage School of Chemical Engineering University of Birmingham

Solar thermochemical energy storage based on calcium looping（CaL） process is a promising technology for next-generation concentrated solar power（CSP） systems. However, conventional calcium carbonate（CaCO3. pellets suffer from slow reaction kinetics, poor stability, and low solar absorptance. Here, we successfully realized high power density and highly stable solar thermochemical energy storage/release by synergistically accelerating energy storage/release via binary sulfate and promoting cycle stability, mechanical strength, and solar absorptance via Al±Mn±Fe oxides. The energy storage density of proposed CaCO3.ellets is still as high as 1455 kJ kg-1with only a slight decay rate of 4.91% over 100 cycles, which is higher than that of state-of-the-art pellets in the literature, in stark contrast to 69.9% of pure CaCO3.ellets over 3.cycles. Compared with pure CaCO3. the energy storage power density or decomposition rate is improved by 12.% due to lower activation energy and promotion of Ca2.diffusion by binary sulfate. The energy release or carbonation rate rises by 10% because of high O2.transport ability of molten binary sulfate. Benefiting from fast energy storage/release rate and high solar absorptance, thermochemical energy storage efficiency is enhanced by more than 50% under direct solar irradiation. This work paves the way for application of direct solar thermochemical energy storage techniques via achieving fast energy storage/release rate, high energy density, good cyclic stability, and high solar absorptance simultaneously.

关键词： Calcium looping (CaL) Solar thermochemical Energy storage Binary sulfate Fast reaction kinetics

Identification and Categorization of Horizontally Transferred Genes in Prokaryotic Genomes

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Acta Biochimica et Biophysica Sinica 2005年第8期37卷 561-566页

作者： Shuo-Yong SHI~1 Xiao-Hui CAI~1 and Da-fu ding~(1,2.) Key Laboratory of Proteomics.Institute of Biochemistry and Cell Biology.Shanghai Institutes for Biological sciences,Chinese Academy of sciences,Gra{3.ate school of the Chinese Academy of sciences.Shanghai 2.003.,china ~2.school of Life science & technology.Shanghai Jiaotong university.Shanghai 2.003..china KeyLaboratoryofProteomics InstituteofBiochemistryandCellBiologyShanghaiInstitutesforBiologicalSciencesChin

Horizontal gene transfer(HGT),a process through which genomes acquire genetic materialsfrom distantly related organisms,is believed to be one of the major forces in prokaryotic genome ***,systematic investigation is still scarce to clarify two basic issues about HGT:(1) what types ofgenes are transferred:and(2.what influence HGT events over the organization and evolution of ***-scale investigations of these two issues will advance the systematical understanding ofHGT in the context of prokaryotic genome *** investigated 82.genomes,we constructed anHGT database across broad evolutionary *** identified four function categories containing a highproportion of horizontally transferred genes:cell envelope,energy metabolism,regulatory functions,andtransport/binding *** biased function distribution indicates that HGT is not completely random;instead,it is under high selective pressure,required by function restraints in ***,wemapped the transferred genes onto the connectivity structure map of organism-specific pathways listed inKyoto Encyclopedia of Genes and Genomes(KEGG).Our results suggest that recruitment of transferredgenes into pathways is also selectively constrained because of the tuned interaction between original *** organization structures still conserve well through evolution even with the recruitment ofhorizontally transferred ***,in pathways whose organization were significantly affected byHGT events,the operon-like arrangement of transferred genes was found to be *** resultssuggest that operon plays an essential and directional role in the integration of alien genes into pathways.

关键词： genome evolution horizontal gene transfer function and pathway analysis

A comprehensive aerodynamic-thermalmechanical design method for fast response turbocharger applied in aviation piston engines

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Propulsion and Power Research 2024年第2期13卷 145-165页

作者： Yu Zhou Yue Song Shuai Zhao Xueyu Li Longtao Shao Huansong Yan {2. Xu Shuiting {3. Research Institute of Aero-Engine Beihang UniversityBeijing 100083China Aircraft/Engine Integrated System Safety beijing Key Laboratory Beijing 100083China school of Energy and Power Engineering Beihang UniversityBeijing 100083China school of Transportation science and Engineering Beihang UniversityBeijing 100083China AVIC Nanjing Engineering Institute of Aircraft Systems Nanjing 210000China Hangzhou International Innovation Institute Beihang UniversityHangzhou 311115China Civil Aviation university of china Tianjin 300300China

Limited by the poor transient response performance of turbochargers,the dynamic performance of aviation piston engines tends to *** a bid to enhance the turbocharger’s acceleration capabilities,this study scrutinizes various factors impacting its *** on the operational principles and transient response process of the turbocharger,three types of in-ertiadnamely,aerodynamic inertia(ADI),thermal inertia(TI),and mechanical inertia(MI)d are identiﬁed and addressed for *** begin,this paper pioneers the innovative deﬁnition of a method for evaluating the transient response performance of the *** method incor-porates the introduction of an ADI parameter,inspired by the deﬁnition of ***,a thin-walled volute design with a low Biot number and a lightweight turbine impeller is introduced to reduce the turbocharger’s TI and *** simulation results of theﬂowﬁeld distribution within the volute and diffuser demonstrate the comprehensive design method’s effectiveness in improving gas pressure and temperature distributions in these ***,the pressure distributionﬂuctuation in the constant moment-of-momentum volute(CMV)is 62.8%lower than that in the constant velocity moment volute(CVMV).The low-TI thin-walled volute not only en-hances the turbocharger’s response speed but also reduces its weight by approximately 40%.The impact of three types of inertia on the engine’s response speed is quantiﬁed as follows:ADI(94%)>MI(5%)>TI(1%).This conclusion has been veriﬁed through test results of both the turbocharger and the *** design method not only signiﬁcantly improves the turbo-charger’s response performance but also offers valuable insights for the optimal design of other blade mechanical systems.

关键词： Turbocharger Fast response design method Aerodynamic inertia Thermal inertia Mechanical inertia

Critical Solvation Structures Arrested Active Molecules for Reversible Zn Electrochemistry

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Nano-Micro Letters 2024年第8期16卷 64-78页

作者： Junjie zheng Bao Zhang Xin Chen Wenyu hao Jia Yao Jingying Li Yi Gan Xiaofang Wang Xingtai Liu Ziang Wu Youwei Liu Lin Lv Li Tao Pei Liang Xiao Ji hao Wang Houzhao Wan Hubei Yangtze Memory Laboratories Wuhan 430205People’s Republic of China Hubei Key Laboratory of Micro‑Nanoelectronic materials and Devices School of MicroelectronicsHubei UniversityWuhan 430062People’s Republic of China school of Physical and Mathematical sciences Nanyang Technological UniversitySingapore 637371Singapore school of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Institute of Optoelectronics technology China Jiliang UniversityHangzhou 310018People’s Republic of China

Aqueous Zn-ion batteries(AZIBs)have attracted increasing attention in next-generation energy storage systems due to their high safety and ***,the side reactions,dendrites and hydrogen evolution effects at the zinc anode interface in aqueous electrolytes seriously hinder the application of aqueous zinc-ion ***,we report a critical solvation strategy to achieve reversible zinc electrochemistry by introducing a small polar molecule acetonitrile to form a“catcher”to arrest active molecules(bound water molecules).The stable solvation structure of[Zn(H_(2.O)_(6)]^(2.)is capable of maintaining and completely inhibiting free water ***[Zn(H_(2.O)_(6)]^(2.)is partially desolvated in the Helmholtz outer layer,the separated active molecules will be arrested by the“catcher”formed by the strong hydrogen bond N-H bond,ensuring the stable desolvation of Zn^(2.).The Zn||Zn symmetric battery can stably cycle for 2.50 h at 1 mAh cm^(-2.,Zn||V_(6)O_(1{2. full battery achieved a capacity retention rate of 99.2.after 10,000 cycles at 10 A g^(-1).This paper proposes a novel critical solvation strategy that paves the route for the construction of high-performance AZIBs.

关键词： Zinc-ion battery Critical solvation Helmholtz layer Arrest active molecule Reversible zinc anode

Experimental Research on Nb bearing X60 Pipeline Steel Produced by CSP Process

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Experimental Research on Nb bearing X60 Pipeline Steel Produ...