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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China

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Petroleum Science 2024年第3期21卷 1488-1507页

作者： Gang Li xian-Ming Xiao Bo-Wei cheng chen-Gang Lu Yue Feng Dong-Sheng Li School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Frontiers Science Center for Deep-time Digital Earth China University of Geosciences(Beijing)Beijing100083 China

The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well *** the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were *** results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM *** pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,*** methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,*** with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption *** GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas *** the geological and geochemical conditions of shale gas formation a

关键词： Lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content Controlling factor

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Recent advances in electrocatalytic generation of indole-derived radical cations and their applications in organic synthesis

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Chinese Chemical Letters 2024年第4期35卷 106-123页

作者： Wei Zhou Xi chen Lin Lu xian-Rong Song Mu-Jia Luo Qiang Xiao Key Laboratory of Organic Chemistry of Jiangxi Province Jiangxi Science&Technology Normal UniversityNanchang 330013China

Indole-derived radical cations, open-shell reactive species, display distinctive dual reactivity due to the carbon-centered radical and more electrophilic carbocation, which frequently appear in a variety of single electron oxidation reactions for synthesizing structurally diverse functionalized indoles and indolines. Electrocatalysis is considered as a synthetically attractive and environmentally friendly alternative for driving the single electron oxidation of indoles. Remarkable achievements in electrocatalytic indolederived radical cation-mediated indole functionalization have been realized so far. This review comprehensively summarizes the recent progresses in the applications of electrocatalytic indole radical cations,including C(sp~2)–H functionalization, dearomative 2,3-difunctionalization, and ring-opening reaction, emphasizing the vital single electron oxidation steps of indoles, the substrates scope and limitations, and the reaction mechanisms.

关键词： Electrocatalysis Indole radical cation C-H functionalizatin Dearomative 2 3-difunctionalization

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Modulated symbol-based one-time pad secure transmission scheme using physical layer keys

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Science China(Information Sciences) 2024年第1期67卷 221-239页

作者： Xiaoyan HU Zheng wan Kaizhi HUANG Liang JIN Mengyao YAN Yajun chen Jinmei YANG Information Engineering University Purple Mountain Laboratories for Network and Communication Security

This paper proposes a novel modulated symbols-based one-time pad(SOTP) secure transmission scheme using physical layer *** classical physical layer key generation and exclusive OR(XOR)encryption in the discrete binary space,we design a framework for modulated symbols-based one-time pad(OTP) encryption,where the cryptographic primitive and mathematical model of SOTP is given to build a practical cryptographic *** with existing physical layer encryption(PLE) schemes,we provide rigorous proof that the framework can meet perfect secrecy and correctness *** addition,we provide a specific scheme of physical layer OTP secure transmission for quadrature amplitude modulation(QAM) and phase-shift keying(PSK) symbols based on physical layer *** scheme realizes the unification of bit encryption and symbol encryption,which can adaptively select the quantization level according to the signal-to-noise ratio(SNR) to minimize the symbol error rate(SER).Further,we analyze the performance quantitatively and derive the closed-form expressions of SER,which indicates that the proposed scheme has a lower ***,simulation results verify that the proposed symbol-wise OTP secure transmission scheme can achieve perfect secrecy and high reliability.

关键词： physical layer security one-time pad wireless channel physical layer encryption perfect secrecy

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Efficient overall photosynthesis of H_(2)O_(2) by the BTz@Mn_(0.2)Cd_(0.8)S S-scheme heterojunction

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Science China Chemistry 2024年第6期67卷 1953-1960页

作者： Zhongyue chen Sijie wan Bei cheng wang wang Yao xiang Jiaguo Yu Shaowen Cao State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China Hubei Technology Innovation Center for Advanced Composites Wuhan University of TechnologyWuhan430070China Hospital of Wuhan University of Technology Wuhan University of TechnologyWuhan430070China Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430074China

The photosynthesis of hydrogen peroxide(H_(2)O_(2))through the selective 2e^(-)oxygen reduction reaction(ORR)from O_(2)and H_(2)O stands out as an environmentally sustainable and cost-effective method for generating this essential ***,the widespread application of most photocatalysts is impeded by their reliance on sacrificial *** this context,we present a noteworthy advancement in the form of a step-scheme(S-scheme)heterojunction involving a donor-acceptor(D-A)-conjugated polymer and manganese cadmium sulfide(BTz@MCS).This innovative configuration enables efficient photocatalytic H_(2)O_(2)production within a non-sacrificial system,showcasing an impressive H_(2)O_(2)yield of 5,368μmol g^(-1)h^(-1)and an apparent quantum yield of 4.5%at 420 *** insights gained from in-situ irradiated X-ray photoelectron spectroscopy(ISIXPS),in-situ diffuse reflectance infrared Fourier transformations spectroscopy(DRIFTS),and density function calculations(DFT),it is revealed that the sp^(2)C between thiazole-thiazole rings at the BTz and the concentrated holes at the MCS function as spatially separated redox *** centers catalyze the selective 2e^(-)ORR and 4e^(-)water oxidation reaction(WOR)*** O_(2)generated from the WOR is subsequently utilized by the ORR cycle,enabling the overall photosynthesis of H_(2)O_(2)with accelerated total reaction ***,the high photocatalytic performance of the developed catalyst is attributed to well-designed S-scheme heterojunctions with tuned band *** spatially separated redox centers and effective transfer of photogenerated charge carriers facilitated by the internal electric field significantly enhance reaction *** study introduces a promising avenue for photocatalytic H_(2)O_(2)production without sacrificial agents,providing valuable insights into the underlying mechanisms in S-scheme heterojunctions.

关键词： hydrogen peroxide non-sacrificial redox centers S-scheme heterojunction

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Molecular-scale co-assembly membranes derived from keplerate cluster:carbonic anhydrase-mimicking nanocapsules for enhanced CO_(2)/N_(2)separation

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Science China Chemistry 2024年第10期67卷 3271-3282页

作者： wan-Lei Zhao Hongqiang Li Ruoxuan Zheng Yixin Yang Wei chen Yu-Fei Song State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Quzhou Institute for Innovation in Resource Chemical Engineering Quzhou 324000China

The development of CO_(2)separation membranes with high permeability and high selectivity,as well as ultra-thin selective layers,has always been ***,a molecular-scaled co-assembly strategy is employed to fabricate the Pebax-Mo_(132)(Pebax=polyether-block-amide copolymer;Mo_(132)=(NH_(4))_(42)[Mo_(72)^(Ⅵ)Mo_(60)^(Ⅴ)O_(372)(CH_(3)COO)_(30)(H_(2)O)_(72)])*** optimal selfstanding membrane,Pebax-Mo_(132)-5%,shows a CO_(2)permeability of~384 Barrer and an ultra-high ideal CO_(2)/N_(2)selectivity of~244,outperforming most membranes reported in the *** CO_(2)permeability and ideal CO_(2)/N_(2)selectivity are increased by 70%and 367%,respectively,compared with the pristine Pebax membrane.A thin-film composite membrane prepared by spin-coating technique on a support membrane with gutter layers also exhibits a CO_(2)permeance of 838 GPU and a CO_(2)/N_(2)selectivity of *** excellent performance can be attributed to the following reasons:(1)strong hydrogen bonding interactions between{Mo_(132)}clusters and Pebax confer excellent interfacial compatibility to the mixed matrix membranes;(2)incorporation of hollow{Mo_(132)}clusters into the Pebax molecular chain decreases the crystallinity of Pebax,and thereby accelerates the chain dynamics and increases the free volume of the membrane;(3)in situ diffuse reflectance infrared Fouriertransform spectroscopy demonstrates that the{Mo_(132)}clusters can effectively catalyze the hydration reaction of CO_(2)and promote the transport of CO_(2);(4)furthermore,the 0.35 nm pores of the crown ether-type{Mo_(9)O_(9)}allow the accurate size sieving of CO_(2)(0.33 nm)and N_(2)(0.36 nm)molecules.

关键词： polyoxometalates molecular-scale assembly CO_(2)capture mixed matrix membranes

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High-speed flexible near-infrared organic photodiode for optical communication

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National Science Review 2024年第3期11卷 227-238页

作者： Yu Zhu Hongbin chen Ruiman Han Hao Qin Zhaoyang Yao Hang Liu Yanfeng Ma xiangjian wan Guanghui Li Yongsheng chen The Centre of Nanoscale Science and Technology and Key Laboratory of Functional Polymer Materials Institute of Polymer ChemistryTianjin Key Laboratory of Functional Polymer Materials College of Chemistry and Renewable Energy Conversion and Storage Center(RECAST) Nankai University State Key Laboratory of Elemento-Organic Chemistry Nankai University

Optical communication is a particularly compelling technology for tackling the speed and capacity bottlenecks in data communication in modern society. Currently, the silicon photodetector plays a dominant role in high-speed optical communication across the visible-near-infrared spectrum. However, its intrinsic rigid structure, high working bias and low responsivity essentially limit its application in next-generation flexible optoelectronic devices. Herein, we report a narrow-bandgap non-fullerene acceptor（NFA） with a remarkable π-extension in the direction of both central and end units（CH17） with respect to the Y6 series, which demonstrates a more effective and compact 3D molecular packing, leading to lower trap states and energetic disorders in the photoactive film. Consequently, the optimized solution-processed organic photodetector（OPD） with CH17 exhibits a remarkable response time of 91 ns（λ = 880 nm） due to the high charge mobility and low parasitic capacitance, exceeding the values of most commercial Si photodiodes and all NFA-based OPDs operating in self-powered mode. More significantly, the flexible OPD exhibits negligible performance attenuation（<1%） after bending for 500 cycles, and maintains 96% of its initial performance even after 550 h of indoor exposure. Furthermore, the high-speed OPD demonstrates a high data transmission rate of 80 MHz with a bit error rate of 3.5 × 10-4, meaning it has great potential in next-generation high-speed flexible optical communication systems.

关键词： flexible organic photodetector high-speed NIR organic photodetector optical communication light fidelity narrow-bandgap non-fullerene acceptors

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Analysis of SF6 decomposed products by fibre-enhanced Raman spectroscopy for gas-insulated switchgear diagnosis

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High Voltage 2024年第1期9卷 206-216页

作者： Jianxin wang Weigen chen Pinyi wang Fu wan Zhixian Zhang Shoufei Gao Yingying wang School of Electrical Engineering Chongqing UniversityChongqingChina State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina Institute of Photonics Technology Jinan UniversityGuangzhouChina

Sulphur hexafluoride(SF6)decomposed products analysis is highly critical in the earlystage fault diagnosis of gas-insulated switchgear(GIS).Spectrum technology outperforms traditional methods on non-invasiveness,no sample preparation,and no ***,the authors present an improved fibre-enhanced Raman spectroscopy(FERS)as a comprehensive analytical tool to detect a suite of SF_(6)decomposed products(SO_(2)F_(2),SOF_(2),SO_(2),H_(2)S,CF_(4),OCS,CO_(2),and CO).The FERS approach is combined with two iris diaphragms for spatial filtering and a rear-end reflector for additional Raman signal *** of detection down to 1×10^(−6)–8×10^(−6)are achieved for different SF6 decompositions,and quantification of an undefined multigas,sampled from an 800 kV GIS in service,is realised utilising SF6 as the internal standard gas and with a maximum error of 5.5%.The GIS is diagnosed according to the results and confirmed by an on-site *** authors foresee that this technique will provide a route for trace gas analysis in the power industry.

关键词： SF6 diagnosis fibre

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Influence of ion size on the charge storage mechanism of MXenes:a combination of experimental and computational

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Waste Disposal and Sustainable Energy 2024年第2期6卷 163-171页

作者： Huiwen wan Rui wang Huiyang Fan Hongbo Gao Yucheng chen Zhu Liu State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringCollege of Energy EngineeringZhejiang UniversityHangzhou 310027China China North Vehicle Research Institute No.4 HuaishulingFengtai DistrictBeijingChina ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang UniversityHangzhou 311215China

MXene nanomaterials have attracted great interest as the electrode of ***,its energy storage mecha-nisms in organic electrolytes are still *** work investigated the size effect of cations(i.e.,Lit,Nat,K^(+),and EMIM^(+))on the capacitive behaviors of MXene-based *** experimental results demonstrate that the specific capacitance increases obviously with decreasing cation size(i.e.,from 43 F g^(-1)(EMIM^(+))to 129 F g^(-1)(Li^(+))at 2 mV s^(-1)).Density-functional theory calculation reveals a correlation between cation size and ion-electrode surface interaction,sup-porting experimental observations of the capacitive-dominant *** dynamics simulations reveal that the ionic solvation structure and desolvation degree of intercalated cations as a function of solvation size,providing dynamic insights into the experimentally observed specific capacitance *** comprehensive experimental and computational study provides valuable insights into the intricate solvation effects governing the charge storage *** finding of ion dynamics,solvation structure,and desolvation may contribute to guide the design and optimization of appropriate ions/electrolytes combinations for MXene-based supercapacitors.

关键词： MXene Cations Molecular dynamics simulation Density-functional theory calculation Supercapacitors

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Impact of nutritional support on immunity,nutrition,inflammation,and outcomes in elderly gastric cancer patients after surgery

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World Journal of Gastrointestinal Surgery 2024年第7期16卷 2175-2182页

作者： Xiao-wan chen Xiao-Chun Guo Fen cheng Department of Gastrointestinal Surgery Hubei Cancer HospitalWuhan 430079Hubei ProvinceChina Department of Gastroenterology The First People’s Hospital of Jiangxia DistrictWuhan 430200Hubei ProvinceChina

BACKGROUND Postoperative rehabilitation of elderly patients with gastric cancer has always been the focus of clinical *** the intervention by a full-course nutritional support team can have a positive impact on the postoperative immune function,nutritional status,inflammatory response,and clinical outcomes of this special population has not yet been fully *** To evaluate the impact of full-course nutritional support on postoperative comprehensive symptoms in elderly patients with gastric *** This is a retrospective study,including 60 elderly gastric cancer patients aged 70 years and above,divided into a nutritional support group and a control *** nutritional support group received full postoperative nutritional support,including individualized meal formulation,and intravenous and parenteral nutrition supplementation,and was regularly evaluated and adjusted by a professional nutrition *** control group received routine postoperative *** After intervention,the proportion of CD4+lymphocytes(25.3%±3.1%vs 21.8%±2.9%,P<0.05)and the level of immunoglobulin G(12.5 G/L±2.3 G/L vs 10.2 G/L±1.8 G/L,P<0.01)were significantly higher in the nutritional support group than in the control group;the changes in body weight(-0.5 kg±0.8 kg vs-1.8 kg±0.9 kg,P<0.05)and body mass index(-0.2±0.3 vs-0.7±0.4,P<0.05)were less significant in the nutritional support group than in the control group;and the level of C-reactive protein(1.2 mg/L±0.4 mg/L vs 2.5 mg/L±0.6 mg/L,P<0.01)and WBC count(7.2×10^(9)/L±1.5×10^(9)/L vs 9.8×10^(9)/L±2.0×10^(9)/L,P<0.01)were significantly lower in the nutritional support group than in the control *** addition,patients in the nutritional support group had a shorter hospital stay(10.3 d±2.1 d vs 14.8 d±3.6 d,P<0.05)and lower incidence of infection(15%vs 35%,P<0.05)in those of the control *** The intervention by the nutritional support team has a positive impact on postoperative immune function,

关键词： Elderly gastric cancer Postoperative Nutritional support Immune function Inflammatory response Clinical outcome

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A defective iron-based perovskite cathode for high-performance IT-SOFCs:Tailoring the oxygen vacancies using Nb/Ta co-doping

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Journal of Energy Chemistry 2024年第1期88卷 306-316,I0008页

作者： Bayu Admasu Beshiwork Xinyu wan Min Xu Haoran Guo Birkneh Sirak Teketel Yu chen Jun Song chen Tingshuai Li Enrico Traversa School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731SichuanChina The Future Laboratory Tsinghua UniversityBeijing 100084China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China Schoolof Environment and Energy South China University of Technlogy Guangzhou 50006GuangongChina Institute for Advanced Study Chengdu UniversityChengdu 610106SichuanChina

The sluggish kinetics of the electrochemical oxygen reduction reaction(ORR)in intermediatetemperature solid oxide fuel cells(IT-SOFCs)greatly limits the overall cell *** this study,an efficient and durable cathode material for IT-SOFCs is designed based on density functional theory(DFT)calculations by co-doping with Nb and Ta the B-site of the SrFeO_(3-δ)perovskite *** DFT calculations suggest that Nb/Ta co-doping can regulate the energy band of the parent SrFeO_(3-δ)and help electron *** symmetrical cells,such cathode with a SrFe_(0.8)Nb_(0.1)Ta_(0.1)O_(3-δ)(SFNT)detailed formula achieves a low cathode polarization resistance of 0.147Ωcm^(2) at 650℃.Electron spin resonance(ESR)and X-ray photoelectron spectroscopy(XPS)analysis confirm that the co-doping of Nb/Ta in SrFeO_(3-δ)B-site increases the balanced concentration of oxygen vacancies,enhancing the electrochemical performance when compared to 20 mol%Nb single-doped perovskite *** cathode button cell with NiSDC|SDC|SFNT configuration achieves an outstanding peak power density of 1.3 W cm^(-2)at 650℃.Moreover,the button cell shows durability for 110 h under 0.65 V at 600℃ using wet H_(2) as fuel.

关键词： Solid oxide fuel cell Cathode Oxygen reduction reaction Power density DFT calculation

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