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Enzymatic C1 reduction using hydrogen in cofactor regeneration

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Frontiers of Chemical Science and Engineering 2024年第7期18卷 33-40页

作者： Ruishuang Sun Chenqi Cao Qingyun Wang Hui Cao Ulrich Schwaneberg Yu ji Luo Liu Haijun xu Beijing Bioprocess Key Laboratory Beijing University of Chemical TechnologyBeijing 100029China Institute of Biotechnology Rheinisch-Westfälische Technische Hochschale(RWTH)AachenAachen 52074Germany

Carbon dioxide fixation presents a potential solution for mitigating the greenhouse gas *** carbon dioxide fixation,C1 compound reduction requires a high energy *** calculations suggest that the energy source for cofactor regeneration plays a vital role in the effective enzymatic C1 *** utilizes renewable hydrogen to achieve the regeneration and supply cofactor nicotinamide adenine dinucleotide(NADH),providing a driving force for the reduction reaction to reduce the thermodynamic barrier of the reaction cascade,and making the forward reduction pathway thermodynamically *** on the regeneration of cofactor NADH by hydrogenase,and coupled with formaldehyde dehydrogenase and formolase,a favorable thermodynamic mode of the C1 reduction pathway for reducing formate to dihydroxyacetone(DHA)was designed and *** resulted in accumulation of 373.19μmol·L^(-1) DHA after 2 h,and conversion reaching 7.47%.These results indicate that enzymatic utilization of hydrogen as the electron donor to regenerate NADH is of great significance to the sustainable and green development of bio-manufacturing because of its high economic efficiency,no by-products,and environment-friendly ***,formolase efficiently and selectively fixed the intermediate formaldehyde(FALD)to DHA,thermodynamically pulled formate to efficiently reduce to DHA,and finally stored the low-grade renewable energy into chemical energy with high energy density.

关键词： [NiFe]-hydrogenase SH formolase NADH regeneration C1 compound reduction thermodynamic calculation

Investigation on combustion and emission characteristics of diesel polyoxymethylene dimethyl ethers blend fuels with exhaust gas recirculation and double injection strategy

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第4期11卷 614-630页

作者： Xin Su Rui Su Nan Gao Hao Chen Zhenhua ji Hongming xu Biao Wang Shaanxi Key Laboratory of New Transportation Energy and Automotive Energy Saving Chang'an University School of Vechicle Engineering Xi'an Aeronautical University Department of Mechanical Engineering University of Birmingham

As a kind of renewable and high oxygen content fuel, polyoxymethylene dimethyl ether（PODE） can be added in diesel to realize energy saving and emissions reduction. To evaluate the combustion and emission characteristics of a diesel engine fueled with diesel and diesel/PODE mixtures, exhaust gas recirculation（EGR） and main-pilot injection strategies with various injection timings were applied. PODE was blended with diesel by volume to form mixtures which were marked as D100（pure diesel）, D90P10（90% diesel + 10% PODE）,and D80P20（80% diesel + 20% PODE）. The results showed that the ignition delay（ID） and combustion duration（CD） of D80P20 were the shortest because of the highest cetane number（CN） and high oxygen content of PODE, indicating more concentrated heat *** low and medium loads, D80P20 achieved the highest peak heat release ratio（PHRR） and peak combustion temperature（PCT） among the three fuels, and it was 14.3% and 3.6%higher than those of D100. PODE blending with diesel can significantly reduce particulate matter（PM） and D80P20 has the lowest PM emissions at all loads. Compared with D100,both PM and nitrogen oxide（NOx） emissions of PODE blends decreased simultaneously with 20% EGR at all loads. With the increase of pilot-main interval, the ID and CD of all test fuels increased, while the NOxand PM emissions decreased. The conclusions of the present research provide a state of the application in light-duty engines fueled with diesel/PODE blends in future work.

关键词： Polyoxymethylene dimethyl ethers Diesel engine NO x Particulate number Pilot plus main injections

Wheel-legged In-pipe Robot with a Bioinspired Hook and Dry Adhesive Attachment Device

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Journal of Bionic Engineering 2024年第3期21卷 1208-1222页

作者： Yahong Liu Yi Sun Kai Cao Shutao Wu Xiaofeng xu Qingfei Han Shikun Wen Huan Shen Guangming Chen jiajun xu Zhiwei Yu Aihong ji Lab of Locomotion Bioinspiration and Intelligent Robots College of Mechanical and Electrical EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In-pipe robots have been widely used in pipes-with smooth inner ***,current in-pipe robots face challenges in terms of moving past obstacles and climbing in marine-vessel pipeline systems,which are affected by marine biofouling and electrochemical *** paper takes inspiration from the dual-hook structure of Trypoxylus dichotomus’s feet and gecko‑like dry adhesives,proposing an in-pipe robot that is capable of climbing on rough and smooth pipe *** combination of the bioinspired hook and dry adhesives allows the robot to stably attach to rough or smooth pipe inwalls,while the wheel-leg hybrid mechanism provides better conditions for obstacle *** paper explores the attachment and obstacle-surmounting mechanisms of the ***,motion strategies for the robot are devised based on different pipe structural *** experiments showed that this robot can adapt to both smooth and rough pipe environments simultaneously,and its motion performance is superior to conventional driving *** robot’s active turning actuators also enable it to navigate through horizontally or vertically oriented 90°bends.

关键词： In-pipe robot Bioinspired attachment device Wheel-legged robot Mechanical design

Colonoscopy plays an important role in detecting colorectal neoplasms in patients with gastric neoplasms

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 133-143页

作者： xu-Rui Liu ze-Lin Wen Fei Liu Zi-Wei Li Xiao-Yu Liu Wei Zhang Dong Peng Department of Gastrointestinal Surgery The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China Department of Gastrointestinal Surgery Yongchuan Hospital of Chongqing Medical UniversityChongqing 402160China

BACKGROUND Gastric cancer(GC)and colorectal cancer(CRC)are the fifth and third most common cancer worldwide,***,GC is reported to have a potential predictive value for CRC,especially for advanced *** To evaluate the necessity of colonoscopy for gastric neoplasm(GN)*** Four databases,including PubMed,EMBASE,the Cochrane Library,and Ovid,were used to perform the search strategy on May 2,*** prevalence of colorectal neoplasms(CRN)and baseline characteristics were compared between the neoplasm group and the control *** variables are expressed as the mean difference and standard *** of categorical variables in the two groups are expressed as odds ratios(OR)and 95%confidence intervals(95%CIs).Subgroup analysis according to different kinds of GNs was conducted for more in-depth *** results of this study are represented by forest *** bias was evaluated by a funnel *** data analyses were performed by STATA SE 16.0 *** A total of 3018 patients with GNs and 3905 healthy controls(age and sex matched)were enrolled for *** comparing the prevalence of CRNs between the two groups,CRNs were detected significantly more frequently in GN patients than in controls(OR=1.69,95%CI=1.28 to 2.23,I^(2)=85.12%,P=0.00),especially in patients with GC(OR=1.80,95%CI=1.49 to 2.18,I^(2)=25.55%,P<0.1).Moreover,other risk factors including age(OR=1.08,95%CI=1.00 to 1.17,I^(2)=90.13%,P=0.00)and male sex(OR=2.31,95%CI=1.26 to 4.22,I^(2)=87.35%,P=0.00),were related to the prevalence of *** patients in the GN group,body mass index(BMI,OR=0.88,95%CI=0.80 to 0.98,I^(2)=0.00%,P=0.92)and smoking(OR=1.03,95%CI=1.01 to 1.05,I^(2)=0.00%,P=0.57)were protective and risk factors for CRNs,*** Patients are recommended to undergo colonoscopy when diagnosed with GNs,especially GC patients with a low BMI and a history of smoking.

关键词： Gastric neoplasm Gastric cancer Colorectal neoplasm Colonoscopy

Improving sulfur transformation of lean electrolyte lithium-sulfur battery using nickel nanoparticles encapsulated in N-doped carbon nanotubes

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Electron 2024年第1期2卷 95-105页

作者： ze Zhang Yuqing xu Donggen Xiong ji Yu jianxin Cai Yizhong Huang Zhenyu Yang School of Chemistry and Chemical Engineering Nanchang UniversityNanchangChina School of Materials Science and Engineering Nanyang Technological UniversitySingaporeSingapore

Efficient redox reactions of lean electrolyte lithium-sulfur(Li-S)batteries highly rely on rational catalyst ***,we report an electrocatalyst based on N-doped carbon nanotubes(CNT)-encapsulated Ni nanoparticles(Ni@NCNT)as kinetics regulators for Li-S batteries to propel the polysulfide-involving multiphase ***,such a CNT-encapsulation strategy greatly prevents the aggregation of Ni nanoparticles and enables the extraordinary structural stability of the hybrid electrocatalyst,which guarantees its persistent catalytic activity on sulfur redox *** used as a modified layer on a commercial separator,the Ni@NCNT interlayer contributes to stabilizing S cathode and Li anode by significantly retarding the shuttle *** corresponding batteries with a 3.5 mg cm^(−2)sulfur loading achieve the promising cycle stability with~85%capacity retention at the electrolyte/sulfur ratios of 5 and 3μL mg^(−1).Even at a high loading of 12.2 mg cm^(−2),the battery affords an areal capacity of 7.5 mA h cm^(−2).

关键词： kinetics regulator lean electrolyte lithium-sulfur battery metal nickel nanoparticles N-doped CNT-encapsulated

Chalcogen-dependent catalytic properties of RuX2 (X = S/Se/Te) nanoparticles decorated carbon nanofibers for hydrogen evolution in acidic and alkaline media

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Nano Research 2024年第4期17卷 2528-2537页

作者： Chengkai He Yue Wei jia xu Yujie Wei Tao Wang Rongfei Liu Lvlv ji Zhun Liu Sheng Wang School of Materials Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China Department of Physics Shaoxing UniversityShaoxing 312000China Zhejiang Kangjiesi New Material Technology Co. LTDZhuji 311800China

Transition metal dichalcogenides(TMDs),with the general formula MX_(2)(M=Mo/W/Fe/Co/Ni,etc.;X=S/Se/Te),have attracted extensive research interests for hydrogen evolution reaction(HER).Compared with numerous studies on noble-metal-free TMDs,the chalcogen-dependent HER catalytic properties of noble-metal-based TMDs are lack of sufficient research ***,a facile electrospinning-assisted synthetic strategy is proposed to synthesize ruthenium dichalcogenides(RuX_(2),X=S/Se/Te)nanoparticles decorated carbon nanofibers(CNFs).Benefiting from the identical nanofibrous morphology and exposed crystal planes of RuX_(2)(111),the catalytic activities of RuX_(2)@CNFs samples were investigated and compared in a fair and direct *** electrochemical measurements coupled with density functional theory calculations were carried out to probe their intrinsic HER catalytic activities,resulting in the catalytic activity order of RuS_(2)@CNFs>RuSe_(2)@CNFs>RuTe_(2)@CNFs in acidic media and that of RuS_(2)@CNFs>RuTe_(2)@CNFs>RuSe_(2)@CNFs in alkaline *** superior catalytic performance of RuS_(2)@CNFs mainly stems from the relative lower HER energy barriers and thereby the higher intrinsic catalytic activity of RuS_(2)(111),leading to ultralow overpotentials of 44 and 9 mV at 10 mA·cm^(-2) in acidic and alkaline media,***_(2)(111)is endowed with the more optimized Gibbs free energy of hydrogen adsorption(ΔGH*)than RuTe_(2)(111),but RuTe_(2)(111)shows enhanced catalytic property for H_(2)O dissociation and OH-desorption than RuSe_(2)(111),therefore,resulting in the altered catalytic activity sequences for RuSe_(2) and RuTe_(2) in acidic and alkaline media.

关键词： hydrogen evolution reaction transition metal dichalcogenides carbon nanofibers electrocatalysis catalytic activity

Fracture sealing performance of granular lost circulation materials at elevated temperature:A theoretical and coupled CFD-DEM simulation study

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Petroleum Science 2024年第1期21卷 567-581页

作者： Chong Lin Qi-Cong xu Lie-Xiang Han Gao Li Hai He Hong-Ling Zhou ji-Ping She CCDC Drilling&Production Technology Research Institute Guanghan618300SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina College of Materials Science and Engineering Chongqing UniversityChongqing400044China State Key Lab of Oil and Gas Reservoir Geology and Exploitation(Chengdu University of Technology) Chengdu610059SichuanChina College of Energy Chengdu University of TechnologyChengdu610059SichuanChina

Lost circulation is a common downhole problem of drilling in geothermal and high-temperature,high-pressure(HTHP)*** circulation material(LCM)is a regular preventive and remedial measure for lost ***,conventional LCMs seem ineffective in high-temperature *** may be due to the changes in the mechanical properties of LCMs and their sealing performance under high-temperature *** understand how high temperature affects the fracture sealing performance of LCMs,we developed a coupled computational fluid dynamics-discrete element method(CFD-DEM)model to simulate the behavior of granular LCMs in *** summarized the literature on the effects of high temperature on the mechanical properties of LCMs and the rheological properties of drilling *** conducted sensitivity analyses to investigate how changing LCM slurry properties affected the fracture sealing efficiency at increasing *** results show that high temperature reduces the size,strength,and friction coefficient of LCMs as well as the drilling fluid ***,softer,and less frictional LCM particles have lower bridging probability and slower bridging *** particles tend to form dual-particle bridges rather than single-particle *** result in a deeper,tighter,but unstable sealing *** drilling fluid viscosity leads to faster and shallower sealing zones.

关键词： Geothermal well drilling HTHP formationLost circulation material CFD-DEM Fracture sealing

Single-cluster electronics using metallic clusters:Fabrications,regulations,and applications

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Nano Research 2024年第1期17卷 65-78页

作者： Caiyun Wei Wei xu Shurui ji Ruiyun Huang Junyang Liu Wenqiu Su jie Bai jiale Huang Wenjing Hong State Key Laboratory of Physical Chemistry of Solid Surfaces National Engineering Research Centre of Chemicals for Electronic ManufacturingCollege of Chemistry and Chemical Engineering&Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(IKKEM)Xiamen UniversityXiamen 361005China

Metallic clusters,ranging from 1 to 2 nm in size,have emerged as promising candidates for creating nanoelectronic devices at the single-cluster *** the intermediate quantum properties between metals and semiconductors,these metallic clusters offer an alternative pathway to silicon-based electronics and organic molecules for miniaturized electronics with dimensions below 5 *** progress has been made in studies of single-cluster electronic ***,a clear guide for selecting,synthesizing,and fabricating functional single-cluster electronic devices is still *** review article provides a comprehensive overview of single-cluster electronic devices,including the mechanisms of electron transport,the fabrication of devices,and the regulations of electron transport ***,we discuss the challenges and future directions for single-cluster electronic devices and their potential applications.

关键词： single-cluster junctions electronic properties electron transport metallic clusters structure regulation

Doping suppresses lattice distortion of vacant quadruple perovskites to activate self-trapped excitons emission

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Nano Research 2024年第4期17卷 3068-3078页

作者： Zhipeng Chen Fei Zhang Dongwen Yang Huifang ji xu Chen Di Wu Xinjian Li Yu Zhang Zhifeng Shi Key Laboratory of Materials Physics of Ministry of Education School of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China

The vacancy-ordered quadruple perovskite Cs_(4)CdBi_(2)Cl_(12),as a newly-emerging lead-free perovskite system,has attracted great research interest due to its excellent stability and direct band ***,the poor luminescence performance limits its application in light-emitting diodes(LEDs)and other ***,for the first time,an Ag^(+)ion doping strategy was proposed to greatly improve the emission performance of Cs_(4)CdBi_(2)Cl_(12) synthesized by hydrothermal *** functional theory calculations combined with experimental results evidence that the weak orange emission from Cs_(4)CdBi_(2)Cl_(12) is attributed to the phonon scattering and energy level crossing due to the large lattice distortion under excited ***,Ag^(+)ion doping breaks the intrinsic crystal field environment of Cs_(4)CdBi_(2)Cl_(12),suppresses the crossover between ground and excited states,and reduces the energy loss in the form of nonradiative *** a critical doping amount of 0.8%,the emission intensity of Cs_(4)CdBi_(2)Cl_(12):Ag^(+)reaches the maximum,about eight times that of the pristine ***,the doped Cs_(4)CdBi_(2)Cl_(12) still maintains excellent stability against heat,ultraviolet irradiation,and environmental oxygen/*** above advantages make it possible for this material to be used as solid-state phosphors for white LEDs applications,and the Commission International de I’Eclairage color coordinates of(0.31,0.34)and high color rendering index of 90.6 were *** importantly,the white LED demonstrates remarkable operation stability in air ambient,showing almost no emission decay after a long working time for 48 *** believe that this study puts forward an effective ion-doping strategy for emission enhancement of vacancy-ordered quadruple perovskite Cs_(4)CdBi_(2)Cl_(12),highlighting its great potential as efficient emitter compatible for practical applications.

关键词： Cs_(4)CdBi_(2)Cl_(12) self-trapped excitons ion doping emission enhancement stability