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China Ocean Engineering 2023年第5期37卷 876-884页

作者： DING Yue ZHAI Gang-jun MA Zhe wei zi-hao LI Xin State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China Faculty of Infrastructure Engineering Dalian University of TechnologyDalian 116024China

To study the water absorption of hollow glass microspheres(HGMs)composite epoxy resin solid buoyancy materials in the marine environment and its effect on the mechanical properties,the water absorption was measured by immersing the material in distilled water for 36 days at ambient temperature and fitted to Fick’s second law.The strength of materials before and after water absorption were tested by uniaxial experiments,and the effects of the filling ratio and water absorption on the mechanical properties of the materials were analyzed and explained.Finally,the failure modes and mechanism of the hollow glass microspheres composite material were explicated from the microscopic level by scanning electron microscope(SEM).This research will help solve the problems of solid buoyancy materials in ocean engineering applications.

关键词： solid buoyancy material water absorption mechanical property failure mechanism scanning electron microscope

河北省肉牛养殖高质量发展评价体系构建及测度

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河北农业科学 2024年第2期28卷 87-94页

作者：王宇航魏子昊崔姹河北农业大学经济管理学院河北保定071000

为了科学设计指标体系评价及测度肉牛养殖高质量发展水平,从养殖高效、生产安全、绿色发展及福利提升4个维度,构建了肉牛养殖高质量发展评价指标体系;并基于河北省肉牛养殖微观调研数据,采用熵权法对其发展程度进行了研究。结果表明:(1)... 详细信息

为了科学设计指标体系评价及测度肉牛养殖高质量发展水平,从养殖高效、生产安全、绿色发展及福利提升4个维度,构建了肉牛养殖高质量发展评价指标体系;并基于河北省肉牛养殖微观调研数据,采用熵权法对其发展程度进行了研究。结果表明:(1)2019-2022年河北省肉牛养殖高质量发展水平波动上升,且内部发展不平衡。养殖高效维度、生产安全维度是综合得分提升的主要驱动力;福利提升维度是阻碍因素。(2)不同规模养殖户肉牛养殖高质量发展水平差异较大,大规模养殖户的肉牛养殖高质量综合得分最高,小规模养殖户的肉牛养殖高质量综合得分最低。散养、小规模养殖户肉牛养殖高质量发展的主要驱动因素为绿色发展和养殖高效;中规模、大规模养殖户肉牛养殖高质量发展的主要驱动因素为养殖高效和生产安全。(3)劳动生产率、机械化水平与出栏率是养殖高效维度提升的主要驱动力,发病率与死亡率是安全生产维度提升的主要驱动力,种养平衡率与粪污还田能力是绿色发展维度提升的主要驱动力,现代化设备投入水平是福利提升维度的主要驱动因素。头均收益、饲料报酬率、防疫周期、废弃物资源化利用水平和饲养密度是4个维度提升的制约因素。饲料报酬率与肉牛出栏率、防疫周期、种养平衡率和粪污还田能力、现代化设备水平是散养户、小规模养殖户4个维度提升的主要驱动力,平均日增重、死亡率和发病率、废弃物资源化利用水平、饲养密度分别是制约因素;劳动效率、死亡率和发病率、资源利用强度、现代化设备水平是中大规模养殖户4个维度提升的主要驱动力,平均日增重、防疫周期、种养平衡率、饲养密度是制约因素。提出以种养结合为抓手,推进肉牛养殖绿色高效发展;提高肉牛养殖现代化发展水平;引导中小规模养殖户提升养殖高质量发展水平的对策建议。

关键词：河北省肉牛养殖高质量发展熵权法

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Dynamical switchable quantum nonreciprocity induced by off-resonant chiral two-photon driving

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 31-37页

作者： Da-wei Liu zi-hao Li Shi-Lei Chao Ying Wu Liu-Gang Si School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Optical nonreciprocity,which refers to the direction-dependent emission,scattering and absorption of photons,plays a very important role in quantum engineering and quantum information processing.Here,we propose an all-optical approach to achieve the optical dynamical switchable quantum nonreciprocity by an off-resonant chiral two-photon driving in a single microring cavity,which differs from the conventional nonreciprocal schemes.It is shown that the optical field with time-dependent statistical properties can be generated and the nonreciprocity flips periodically,with switchable photon blockade and photon-induced tunneling effects.We find that the dynamical system is robust and immune to the parameter variations,which loosens the parameter range of system.Meanwhile,the time window for one-way quantum information is sufficiently wide and tunable.Our work opens a new idea for the current quantum nonreciprocal research,which can facilitate a memory functionality and be used for future inmemory superconducting quantum compute.The other nonreciprocal quantum devices,i.e.,dynamical switchable nonreciprocal squeezing and entanglement,may be inspired by our method,which is expected to have important applications in future quantum technology.

关键词： dynamical switchable nonreciprocity single-photon source chiral two-photon driving

Influence of sintering time on microstructure and properties of hot oscillatory pressing sintered W–Cu refractory alloys

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Tungsten 2024年第2期6卷 323-332页

作者： zi-Qian Wu wei Zhao Ka Gao Shi-hao Du Qing-Quan Kong De-Jian Sun Yang Gao School of Materials Science and Engineering Zhengzhou University of AeronauticsZhengzhou 450015China School of Mechanical Engineering University of Shanghai for Science and TechnologyShanghai 200093China Department of General Medicine Changhai HospitalShanghai 200000China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and TechnologyWuhan 430081China Sichuan Province Engineering Technology Research Center of Powder Metallurgy Chengdu UniversityChengdu 610106China

W–Cu refractory alloys are widely used in aerospace,aviation,electronics,power,and other fi elds.However,because of its large melting point diff erence between alloy elements,the conventional powder metallurgy method required a long time of high temperature sintering is very likely to cause low density and abnormal grain size growth.Therefore,90W-10Cu refractory alloys were successfully prepared by hot oscillatory pressing(HOP)under diff erent sintering time in this work.Then the infl uence of sintering time on the microstructure,grain size,density,Vickers hardness,room-tensile property,and electrical conductivity of the W–Cu refractory alloy was systematically invested.The results showed that during the short sintering time(30–90 min),the density,Vickers hardness,tensile strength,and electrical conductivity of the W–Cu refractory alloy increased signifi cantly to 98.7%,163.29 HV 30,507.3 MPa,and 14.2%International Annealed Copper Standard with the sintering time increasing,respectively,while its grain size showed no obvious change.When the sintering time further increased to 120 min,the density was basically consistent with the sintering time of 90 min.Nevertheless,the prolonged high temperature sintering resulted in the grain growth of the samples,which caused the deterioration of the Vickers hardness,room-tensile strength,and conductivity properties of the W–Cu refractory alloy.At the same sintering time,the density,Vickers hardness,and electrical conductivity of the HOP sintered W–Cu refractory alloy were signifi cantly higher than those of the HP sintered sample.It was indicated that high density,fi ne-grain,and excellent properties W–Cu refractory alloys could be prepared by hot oscillatory pressing under appropriate sintering time.

关键词： W–Cu refractory alloy Hot oscillatory pressing Sintering time Microstructure Property

ziF-8 modified by isocyanate as a photocatalytic antibacterial agent

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Rare Metals 2024年第6期43卷 2708-2718页

作者： Yi-Ning Zhang Zhen Pei zi-hao Wang Chong-En Wang Fen-Fen Liang Li-Qiao wei College of Architecture Taiyuan University of Technology Key Laboratory of Interface Science and Engineering in Advanced Materials of Taiyuan University of Technology Ministry of Education Department of Materials Science and Engineering Shanxi Institute of Technology Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering

Zeolite imidazole skeleton（ziF-8） is a promising option for self-cleaning of building exterior walls due to its large specific surface area,high antibacterial activity and low biotoxicity.However,it suffers from low antibacterial efficiency and yield under visible light irradiation.To address the issues,we developed the photocatalytic materials T-ziF-8-TDI（thermally treated-ziF-8-toluene 2,4-diisocyanate） by modifying ziF-8 with thermal oxygen sensitization and chemical bonding.The results show that the yield of T-ziF-8-TDI photocatalytic antibacterial agent is increased to 11.5 times of that of T-ziF-8,while maintaining the crystal structure of T-ziF-8 and thermal stability up to 60℃.Furthermore,T-ziF-8-TDI exhibits extended optical response range to the nearinfrared region,significantly narrowed band gap,improved photogenerated elec tron-hole separation efficiency,reduced recombination rate,and excellent photocatalytic performance.When the concentration of antibacterial agent is 600 mg·L-1,the antibacterial rate of Escherichia coli（E.coli） reaches 99.99% irradiated by visible light for30 min,and when the concentration of antibacterial agent is 200 mg·L-1,the antibacterial rate of Staphylococcus aureus（S.aureus） reaches 99.99% irradiated by visible light for 25 min.We also analyzed the reasons in detail from the aspects of bacterial species and antibacterial mechanism,and proposed the antibacterial mechanism of·O2-and h+as the main active species.These findings suggest that T-ziF-8-TDI photocatalytic antibacterial agent has potential for use in self-cleaning of building exterior walls.

关键词： ziF-8 Hot oxygen sensitization Modified by isocyanate Antimicrobial performance Photocatalytic antibacterial mechanism

Antiviral treatment standards for hepatitis B:An urgent need for expansion

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World Journal of Gastroenterology 2024年第4期30卷 418-420页

作者： zi-Hong Bao Zhi-Kun Dai hao-Xian Tang Department of Infectious Diseases The First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina Medical College Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina Department of Cardiology The First Affiliated Hospital of Shantou University Medical CollegeShantou 515041Guangdong ProvinceChina

The present letter to the editor is related to the review with the title“Past,present,and future of long-term treatment for hepatitis B virus.”Chronic hepatitis B(CHB)represents an important and pressing public health concern.Timely identification and effective antiviral therapy hold the potential to reduce liver-related mortality attributable to chronic infection with hepatitis B virus(HBV)substantially.However,the current global treatment rates for CHB remain conspicuously low,with the excessively stringent treatment criteria advocated by national CHB guidelines being a contributing factor to these low rates.Nevertheless,recent strides in comprehending this malady and the emergence of novel antiviral agents prompt the imperative re-evaluation of treatment standards to extend the sphere of potential beneficiaries.An impending need arises for a novel paradigm for the classification of patients with CHB,the expansion of antiviral treatment eligibility for HBV-infected individuals,and even the streamlining of the diagnostic process for CHB to amplify cost-effectiveness and augment survival prospects.

关键词： Hepatitis B virus Chronic hepatitis B Antiviral treatment criteria Serum alanine aminotransferase Liver-related mortality Letter to the Editor

Enhancing force sensing in a squeezed optomechanical system with quantum nondemolition measurement

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Communications in Theoretical Physics 2024年第1期76卷 49-60页

作者： Shi-Lei Chao zi-hao Li Xin-You Lü School of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical scheme is proposed to enhance the sensitivity of force sensors with quantum nondemolition measurement(QND)in an optomechanical setup assisted by four-tone optical driving and an optical parametric amplifier(OPA).With the help of special drive,the system can be simplified as the typical type of QND for force sensing,so that the backaction noise can be evaded to surpass the standard quantum limit.Besides,the added noise can be suppressed owing to the modified optical susceptibility resulting from the OPA.By introducing two oscillators coupling with two charged bodies respectively,the signal can be enhanced with the nonlinearity caused by Coulomb interaction,while the noise presents an exponential decrease.Moreover,considering the homodyne detection effect,the range of system parameters and frequency bands will be broadened.The present investigation may provide a route toward simultaneously evading backaction noise,reducing the mechanical thermal noise,and enhancing the external signal,which can be an alternative design for sensitive devices.

关键词： force sensing optical parametric amplifier quantum non-demolition measurement optomechanical system

Nonreciprocal generation of Schrodinger cat state induced by topology

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 23-30页

作者： zi-hao Li Li-Li Zheng Ying Wu Xin-You Lü School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and Technologyand Wuhan Institute of Quantum TechnologyWuhan 430074China Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education Jianghan UniversityWuhan 430074China

The Schrodinger cat state produced differently in two directions is anticipated to be a critical quantum resource in quantum information technologies.By exploring the interplay between quantum nonreciprocity and topology in a one-dimensional microcavity array,we obtain the Schrodinger cat state(a pure quantum state)in a chosen direction at the edge cavity,whereas a classical state in the other direction.This nonreciprocal generation of the cat state originates from the topologically protected chiralitymode excitation in the nontrivial phase,but in the trivial phase,the nonreciprocal generation of cat state vanishes.Thus,our proposal is switchable by tuning the parameters so that a topological phase transition occurs.Moreover,the obtained cat state has nonreciprocal high fidelity,nonclassicality,and quantum coherence,which are sufficient to be used in various one-way quantum technologies,e.g.,invisible quantum sensing,noise-tolerant quantum computing,and chiral quantum networks.Our work provides a general approach to control quantum nonreciprocities with the topological effect,which substantially broadens the fields of nonreciprocal photonics and topological physics.

关键词： Schr?dinger cat state nonreciprocity topology

Optimization of Hydrocracking Process for Enhanced BTX Production from Coal Tar-Derived Hydrorefined Products

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 139-151页

作者： Wu hao wei Hongyuan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China SINOPEC Research Institute of Petroleum Processing Co. Ltd.Beijing 100083China

Hydroconversion of coal tar to produce aromatic hydrocarbons(BTX)represents a crucial strategy for the highvalue hierarchical utilization of coal.This study focused on the hydrocracking of hydrorefined products derived from coal tar to enhance the production of benzene,toluene,and xylene(BTX).Various reaction conditions,including reaction temperature,hydrogen pressure,space velocity,and hydrogen-to-oil volume ratio,were systematically explored to optimize BTX yields while also considering the process’s economic feasibility.The results indicate that increasing the reaction temperature from 360℃ to 390℃ significantly favors the production of BTX,with yields increasing from 21.42%to 41.14%.Similarly,an increase in hydrogen pressure from 4 MPa to 6 MPa boosts BTX production,with yields rising from 36.31%to 41.14%.Reducing the space velocity from 2 h^(-1) to 0.5 h^(-1) also favors the BTX production process,with yields increasing from 37.96%to 45.13%.Furthermore,raising the hydrogen-to-oil volume ratio from 750 to 1500 improves BTX yields from 41.61%to 45.44%.Through economic analysis,the optimal conditions for BTX production were identified as a reaction temperature of 390℃,hydrogen pressure of 5-6 MPa,space velocity of 1 h^(-1),and hydrogen-to-oil volume ratio of 1000,achieving a BTX yield of 43.73%.This investigation highlights the importance of a holistic evaluation of hydrocracking conditions to optimize BTX production.Furthermore,the findings offer valuable insights for the design and operation of industrial hydrocracking processes aimed at efficiently converting coal tar-derived hydrorefined feedstock into BTX.

关键词： coal tar hydrocracking BTX process optimization economic assessment

Computed tomography radiogenomics:A potential tool for prediction of molecular subtypes in gastric stromal tumor

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1296-1308页

作者： Xiao-Nan Yin zi-hao Wang Li Zou Cai-wei Yang Chao-Yong Shen Bai-Ke Liu Yuan Yin Xi-Jiao Liu Bo Zhang Gastric Cancer Research Center West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Paediatric Surgery West China Hospital of Sichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Radiology West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Gastrointestinal Surgery Sichuan University West China HospitalChengdu 610041Sichuan ProvinceChina

BACKGROUND Preoperative knowledge of mutational status of gastrointestinal stromal tumors(GISTs)is essential to guide the individualized precision therapy.AIM To develop a combined model that integrates clinical and contrast-enhanced computed tomography(CE-CT)features to predict gastric GISTs with specific genetic mutations,namely KIT exon 11 mutations or KIT exon 11 codons 557-558 deletions.METHODS A total of 231 GIST patients with definitive genetic phenotypes were divided into a training dataset and a validation dataset in a 7:3 ratio.The models were constructed using selected clinical features,conventional CT features,and radiomics features extracted from abdominal CE-CT images.Three models were developed:ModelCT sign,modelCT sign+rad,and model CTsign+rad+clinic.The diagnostic performance of these models was evaluated using receiver operating characteristic(ROC)curve analysis and the Delong test.RESULTS The ROC analyses revealed that in the training cohort,the area under the curve(AUC)values for model_(CT sign),model_(CT sign+rad),and modelCT_(sign+rad+clinic)for predicting KIT exon 11 mutation were 0.743,0.818,and 0.915,respectively.In the validation cohort,the AUC values for the same models were 0.670,0.781,and 0.811,respectively.For predicting KIT exon 11 codons 557-558 deletions,the AUC values in the training cohort were 0.667,0.842,and 0.720 for model_(CT sign),model_(CT sign+rad),and modelCT_(sign+rad+clinic),respectively.In the validation cohort,the AUC values for the same models were 0.610,0.782,and 0.795,respectively.Based on the decision curve analysis,it was determined that the model_(CT sign+rad+clinic)had clinical significance and utility.CONCLUSION Our findings demonstrate that the combined modelCT_(sign+rad+clinic)effectively distinguishes GISTs with KIT exon 11 mutation and KIT exon 11 codons 557-558 deletions.This combined model has the potential to be valuable in assessing the genotype of GISTs.

关键词： Gastrointestinal stromal tumor Radiomics Gene mutation Computed tomography Model