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Multiple damage zones around hydraulic fractures generated by high-frequency pulsating hydraulic fracturing

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Petroleum Science 2024年第4期21卷 2688-2702页

作者： Yan Peng sheng-jie Wei Guang-Qing Zhang Da-Wei Zhou Chuang-Chao Xu School of Petroleum Engineering China University of Petroleum PetroChina Changqing Oilfield Company

Pulsating hydraulic fracturing(PHF) is a promising fracturing method and can generate a dynamic periodic pressure. The periodic pressure can induce fatigue failure of rocks and decrease initiation pressure of fracture. If the frequency of periodic pressure exceeds 10 Hz, the distribution of pressure along the main fracture will be heterogeneous, which is much different from the one induced by the common fracturing method. In this study, the impact of this special spatial feature of pressure on hydraulic fracture is mainly investigated. A coupled numerical simulation model is first proposed and verified through experimental and theoretical solutions. The mechanism of secondary fracture initiation around the main fracture is then discovered. In addition, sensitivity studies are conducted to find out the application potential of this new method. The results show that(1) this coupled numerical simulation model is accurate. Through comparison with experimental and theoretical data, the average error of this coupled model is less than 1.01%.(2) Even if a reservoir has no natural fracture, this heterogeneous distribution pressure can also cause many secondary fractures around the main fracture.(3) The mechanism of secondary fracture initiation is that this heterogeneous distribution pressure causes tensile stress at many locations along the main fracture.(4) Through adjusting the stimulation parameters, the stimulation efficiency can be improved. The average and amplitude of pressure can increase possibility of secondary fracture initiation. The frequency of this periodic pressure can increase number of secondary fractures. Even 6 secondary fractures along a 100 m-length main fracture can be generated.(5) The influence magnitudes of stimulation parameters are larger than ones of geomechanical properties, therefore, this new fracturing method has a wide application potential.

关键词： Tight reservoir Reservoir stimulation Numerical simulation Secondary fracture Fracture initiation

Hydrogen-rich surface of MoC catalysts for efficient CO_(2) hydrogenation induced by a coupled hydrogen donator

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Nano Research 2024年第8期17卷 7762-7767页

作者： Dong Xu Si-Yuan Xia Qi-Yuan Li jie-sheng Chen Xin-Hao Li School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Jiao Tong UniversityShanghai 200240China

Direct CO_(2) hydrogenation offers an important strategy for promoting the global carbon balance,but high thermodynamic and kinetic stability of CO_(2) has restricted its applicability to only a handful of industrial ***,we introduce a proof-of-concept application of the electron-rich Pt surface to promote hydrogen donation for electron-rich MoC particles acting as hydrogen acceptors,thereby constructing hydrogen-rich surface of MoC active ***,the formed hydrogen-rich and electronrich surface could greatly decrease reaction activation energy to boost the efficient CO_(2) hydrogenation into formic acid over the MoC *** optimized MoC@NC/Pt-0.1(NC:nitrogen-doped carbon)catalyst exhibits a high turnover frequency(TOF)value of 1.2 h^(−1) at a lower temperature of 60℃and a TOF of 24.2 h^(−1) under standard reaction conditions widely used in the literature,exceeding 7 times of MoC@NC catalyst and surpassing the benchmark classical non-noble metal active center-based heterogeneous catalyst.

关键词： electron-rich Pt nanoparticles hydrogen donation hydrogen-rich MoC nanoparticles CO_(2) hydrogenation formic acid

Féeton(B-L gauge boson)dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux

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Chinese Physics C 2024年第8期48卷 76-82页

作者： jie sheng Yu Cheng Weikang Lin Tsutomu T.Yanagida Tsung-Dao Lee Institute&School of Physics and Astronomy Shanghai Jiao Tong UniversityChina Key Laboratory for Particle Astrophysics and Cosmology(MOE)&Shanghai Key Laboratory for Particle Physics and Cosmology Shanghai Jiao Tong UniversityShanghai 200240China South-Western Institute For Astronomy Research Yunnan UniversityKunming 650500China Kavli IPMU(WPI) UTIASUniversity of TokyoKashiwa277-8583Japan

The féeton is the gauge boson of the U(1)_(B−L) gauge *** the gauge coupling constant is extremely small,the féeton becomes a candidate for dark *** show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent *** féeton dark matter decays mainly into pairs neutrino and *** low-energy experiments with improved directional capability will enable capturing these neutrino *** seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.

关键词： feeton 511-keV gamma-ray excess low-energy neutrino

A novel encoding mechanism for particle physics

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Nuclear Science and Techniques 2024年第8期35卷 153-166页

作者： Zhi‑Guang Tan sheng‑jie Wang You‑Neng Guo Hua Zheng Aldo Bonasera School of Electronic Information and Electrical Engineering Changsha UniversityChangsha 410003China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFN95123 CataniaItaly

This study proposes a novel particle encoding mechanism that seamlessly incorporates the quantum properties of particles,with a specific emphasis on constituent *** primary objective of this mechanism is to facilitate the digital registration and identification of a wide range of particle *** design ensures easy integration with different event generators and digital simulations commonly used in high-energy ***,this innovative framework can be easily expanded to encode complex multi-quark states comprising up to nine valence quarks and accommodating an angular momentum of up to 99/*** versatility and scalability make it a valuable tool.

关键词： Multi-quark state Encoding mechanism Constituent quark Particle physics

How Effective are Decentralized Anti-poverty Programs?

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China & World Economy 2024年第4期32卷 85-113页

作者： Shuai Chen Mingda Cheng jie-sheng Tan-Soo China Academy for Rural Development and School of Public Affairs Zhejiang UniversityChina Jiangxi Caitong Supply Chain Financial Group Co. Ltd.Jiangxi Financial Holding Group Co.Ltd.China Lee Kuan Yew School of Public Policy National University of SingaporeSingapore

This study examines the effectiveness of China's National Poor Counties(NPC)program,a decentralized anti-poverty initiative,by analyzing five rounds of individual-level panel data from 1988 to *** impact of two waves of the NPC program(1994 and 2001)is evaluated utilizing a panel fixed-effects regression *** results indicate substantial positive effects,with residents in NPC counties experiencing a 47 percent income increase,3.1 percent higher employment rates,and a 5.7 percent rise in household expenditure from 1988 to 2008,in comparison with non-NPC ***,the program benefited vulnerable populations,dispelling concerns about"elite capture."The study also reveals that evolving policy focus has played a pivotal role in sustaining the effects of the program over *** 1994 round prioritized low-skilled employment,and the 2001 wave emphasized productivity enhancement through skills *** findings highlight the continued efficacy of decentralized anti-povertyefforts.

关键词： decentralization elite capture National Poor Counties program poverty

Bipolar hip arthroplasty using conjoined tendon preserving posterior lateral approach in treatment of displaced femoral neck fractures

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World Journal of Clinical Cases 2024年第6期12卷 1076-1083页

作者： Ting-Xin Yan sheng-jie Dong Bo Ning Yu-Chi Zhao Department of Joint Surgery Yantaishan HospitalYantai 264003Shandong ProvinceChina Department of Joint Surgery Dongying People's HospitalDongying 257091Shandong ProvinceChina

BACKGROUND Hip fractures account for 23.8%of all fractures in patients over the age of 75 *** than half of these patients are older than 80 *** hemiarthroplasty(BHA)was established as an effective management option for these *** approaches can be used for the BHA ***,there is a high risk of postoperative *** conjoined tendon-preserving posterior(CPP)lateral approach was introduced to reduce postoperative dislocation *** To evaluate the effectiveness and safety of the CPP lateral approach for BHA in elderly *** We retrospectively analyzed medical data from 80 patients with displaced femoral neck fractures who underwent *** patients were followed up for at least 1 *** the 80 patients,57(71.3%)were *** time to operation averaged 2.3 d(range:1-5 d).The mean age was 80.5 years(range:67-90 years),and the mean body mass index was 24.9 kg/m^(2)(range:17-36 kg/m^(2)).According to the Garden classification,42.5%of patients were typeⅢand 57.5%of patients were typeⅣ.Uncemented bipolar hip prostheses were used for all *** conjoined tendons,dislocations,and adverse complications during and after surgery were *** The mean postoperative follow-up time was 15.3 months(range:12-18 months).The average surgery time was 52 min(range:40-70 min)with an average blood loss of 120 mL(range:80-320 mL).The transfusion rate was 10%(8 of 80 patients).The gemellus inferior was torn in 4 patients(5%),while it was difficult to identify in 2 patients(2.5%)during *** posterior capsule was punctured by the fractured femoral neck in 3 patients,but the conjoined tendon and the piriformis tendon remained *** patients had stem varus greater than 3 degrees or femoral *** were no patients with stem subsidence more than 5 mm at the last *** postoperative dislocations were observed throughout the follow-up *** significance was found between preoperative an

关键词： Conjoined tendon preserving Bipolar hip arthroplasty Femoral neck fractures Postoperative dislocation Posterolateral approach

Machine learning prediction model for gray-level co-occurrence matrix features of synchronous liver metastasis in colorectal cancer

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World Journal of Gastrointestinal Surgery 2024年第6期16卷 1571-1581页

作者： Kai-Feng Yang sheng-jie Li Jun Xu Yong-Bin Zheng Department of Gastrointestinal Surgery Renmin Hospital of Wuhan UniversityWuhan 430030Hubei ProvinceChina Department of Gastrointestinal Surgery The First College of Clinical Medical ScienceChina Three Gorges UniversityYichang Central People’s HospitalYichang 443008Hubei ProvinceChina

BACKGROUND Synchronous liver metastasis(SLM)is a significant contributor to morbidity in colorectal cancer(CRC).There are no effective predictive device integration algorithms to predict adverse SLM events during the diagnosis of *** To explore the risk factors for SLM in CRC and construct a visual prediction model based on gray-level co-occurrence matrix(GLCM)features collected from magnetic resonance imaging(MRI).METHODS Our study retrospectively enrolled 392 patients with CRC from Yichang Central People’s Hospital from January 2015 to May *** were randomly divided into a training and validation group(3:7).The clinical parameters and GLCM features extracted from MRI were included as candidate *** prediction model was constructed using a generalized linear regression model,random forest model(RFM),and artificial neural network *** operating characteristic curves and decision curves were used to evaluate the prediction *** Among the 392 patients,48 had SLM(12.24%).We obtained fourteen GLCM imaging data for variable screening of SLM prediction *** difference,mean sum,sum entropy,sum variance,sum of squares,energy,and difference variance were listed as candidate variables,and the prediction efficiency(area under the curve)of the subsequent RFM in the training set and internal validation set was 0.917[95%confidence interval(95%CI):0.866-0.968]and 0.09(95%CI:0.858-0.960),*** A predictive model combining GLCM image features with machine learning can predict SLM in *** model can assist clinicians in making timely and personalized clinical decisions.

关键词： Colorectal cancer Synchronous liver metastasis Gray-level co-occurrence matrix Machine learning algorithm Prediction model

MOF-derived 1D CGO Cathode for Efficient Solid Oxide Electrolysis Cells

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Chemical Research in Chinese Universities 2024年第4期40卷 737-746页

作者： TIAN Jiayu SUN Qi LIU Pei DAI Jiuyi CAI Yezheng XU Miao YE Tian-Nan CHEN jie-sheng Frontiers Science Center for Transformative Molecules School of Chemistry and Chemical EngineeringShanghai Jiao Tong UniversityShanghai200240P.R.China Zhangjiang Institute for Advanced Study Shanghai Jiao Tong UniversityShanghai200240P.R.China State Key Laboratory of Space Power-sources Shanghai Institute of Space Power-sourcesShanghai200245P.R.China

Solid oxide electrolysis cells(SOECs)provide a promising way for converting renewable energy into chemical ***,NiO/CGO(nickel-gadolinium doped ceria)cermet has shown its excellent properties in ionic and electronic conductivity under reducing ***,we developed a novel 1D NiO/CGO cathode through a cerium metal-organic framework(MOF)derived *** cathode’s 1D nanostructure integrated with a microchannel scaffold facilitates enhanced mass transport,providing vertically aligned pathways for CO_(2)and H_(2)O ***,the 1D framework increases the number of interfacial sites and reduces ion diffusion distances,thereby simplifying electron/ion ***,this advanced cathode achieved a significant breakthrough in SOEC performance,maintaining efficient CO_(2)and H_(2)O electrolysis at an extraordinary current density of 1.41 A/cm^(2)at 1.5 V and excellent stability over 24 h at 850℃.The enhanced performance of this newly developed cathode not only achieves a remarkable 100%improvement compared to those of NiO/CGO cathodes with varying geometrical configurations but also surpasses those of commercial NiO/CGO catalysts by an outstanding 40%when tested under identical *** development of the 1D NiO/CGO enhances the efficiency and durability of ceramic cathodes for CO_(2)and H_(2)O co-electrolysis in SOECs and improves the scalability and effectiveness of SOECs in renewable energy applications.

关键词： Cerium metal-organic framework One-dimensional structure Gadolinium doped ceria CO_(2)activation co-Electrolysis

Functional role of circRNA CHRC through miR-431-5p/KLF15 signaling axis in the progression of heart failure

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Journal of Genetics and Genomics 2024年第8期51卷 844-854页

作者： Yi Hu Huaming Cao jie sheng Yizhuo Sun Yuping Zhu Qin Lin Na Yi Siyu He Luying Peng Li Li State Key Laboratory of Cardiology and Medical Innovation Center Shanghai East HospitalTongji University School of MedicineShanghai 200120China Shanghai Arrhythmias Research Center Shanghai East HospitalTongji University School of MedicineShanghai 200120China Laboratory of Molecular Genetics and Stem Cell Differentiation Tongji University School of MedicineShanghai 200120China Department of Cardiology Shanghai Shibei HospitalShanghai 200435China Research Units of Origin and Regulation of Heart Rhythm Chinese Academy of Medical SciencesShanghai 200120China

Pathological myocardial hypertrophy is a common early clinical manifestation of heart failure,with noncoding RNAs exerting regulatory ***,the molecular function of circular RNAs(circRNAs)in the progression from cardiac hypertrophy to heart failure remains *** uncover functional circRNAs and identify the core circRNA signaling pathway in heart failure,we construct a global triple network(microRNA,circRNA,and mRNA)based on the competitive endogenous RNA(ceRNA)*** observe that cardiac hypertrophy-related circRNA(circRNA CHRC),within the ceRNA network,is down-regulated in both transverse aortic constriction mice and Ang-II--treated primary mouse *** circRNA CHRC increases cross-sectional cell area,atrial natriuretic peptide,andβ-myosin heavy chain levels in primary mouse *** screening shows that circRNA CHRC targets the miR-431-5p/KLF15 axis implicated in heart failure progression in vivo and in *** with anti-Ago2-RNA confirms the interaction between circRNA CHRC and miR-431-5p,while miR-431-5p mimics reverse Klf15 activation caused by circRNA CHRC *** summary,circRNA CHRC attenuates cardiac hypertrophy via sponging miR-431-5p to maintain the normal level of Klf15 expression.

关键词： circRNA CHRC Heart failure CeRNA miR-431-4p KIf15