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Uncovering the oxidation mechanism of sphalerite(ZnS)in the absence and presence of water:A first-principles investigation

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International Journal of Mining Science and Technology 2025年第1期35卷 149-157页

作者： Yuanjia Luo wei Sun Haisheng Han Jian Peng feng Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China

Herein,a first-principles investigation was innovatively conducted to research the surface oxidation of ZnS-like sphalerite in the absence and presence of H_(2)O .The findings showed that single O_(2) was preferred to be dissociated adsorption on sphalerite surface by generating SAO and Zn AO bonds,and the S atom on the surface was the most energy-supported site for O_(2) adsorption,on which a≡Zn-O-S-O-Zn≡structure will be ***,dissociated adsorption of single H_(2)O will not *** was preferred to be adsorbed on the top Zn atom on sphalerite surface in molecular form through Zn-O ***,sphalerite oxidation can occur as if O_(2) was present regardless of the presence of H_(2)O ,and when H_(2)O and O_(2) coexisted,the formation of sulfur oxide(SO_(2) )needed a lower energy barrier and it was easier to form on sphalerite surface than that only O_(2) *** the absence of H_(2)O ,when SO_(2) was generated,further oxidation of which would form neutral zinc *** the presence of H_(2)O ,the formation of SO_(2) on sphalerite surface was easier and the rate of further oxidation to form sulfate was also ***,the occurrence of sphalerite oxidation was accelerated.

关键词： First-principles Oxidation Sphalerite H_(2)O Lower energy barrier

Mainchain conformation ordering self-assembly tailored room temperature phosphorescence emission

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Science China Chemistry 2025年第1期68卷 329-336页

作者： Yuzhu Li Yumeng Gao feng Tian Yu Wang Yuan Yao Shaoliang Lin xiang Ma Binbin Xu Shanghai Key Laboratory of Advanced Polymeric Materials Key Laboratory for Ultrafine Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Key Laboratory for Advance Materials and Feringa Noble Prize Scientist Joint Research Centre Frontiers Science for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China

Developing organic room-temperature phosphorescence(RTP)materials with a wide range of tunable-emission is significant in expanding the applications of RTP ***,we rationally designed amphiphilic alternating copolymers poly(1,2-bis(4-alkoxyphenyl)ethane-1,2-dione-alt-(ethylene glycol)x)(P(Bz-alt-EGx))that combined the advantage of alternating benzil and EGxskeleton,and tunable mainchain *** a mainchain conformation ordering assembly(COA)process,P(Bz-alt-EGx)self-assembled into well-defined platelets,and such assemblies emitted blue RTP at ca.425 nm due to the ordered folded-chain conformation and confined *** contrast,traditional self-assembly(TA)of P(Bz-alt-EGx)obtained less ordered aggregates,such as asymmetric worms,vesicles,and rod-like *** resultant less ordered aggregates exhibited yellow-green RTP at ca.550 *** wide-tuning RTP emission in solution(between blue and yellow-green,over125 nm)is realized using the P(Bz-alt-EG_(x))alternating copolymers under the treatment of different self-assembly *** study uncovers a new strategy to tailor the RTP emission through different self-assembly pathways and holds great promise for the fabrication of advanced optical materials.

关键词： self-assembly conformation ordering alternating copolymer phosphorescence emission

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汉语动词连见的计算机处理规则研究

计算机应用研究 2006年第1期23卷 37-40页

作者：韦向峰张全中国科学院研究生院北京100039 中国科学院声学研究所北京100080

基于概念层次网络(HNC)理论,对多动词出现的一种情况———动词连见,进行了分类研究,给出了相应的处理规则。同时,还提出了一种基于BNF范式和产生式规则的形式化规则描述语言,完成了对规则的形式化描述和软件实现。在此基础上,对真实语... 详细信息

基于概念层次网络(HNC)理论,对多动词出现的一种情况———动词连见,进行了分类研究,给出了相应的处理规则。同时,还提出了一种基于BNF范式和产生式规则的形式化规则描述语言,完成了对规则的形式化描述和软件实现。在此基础上,对真实语料中出现动词连见的语句进行了计算机自动处理,给出了处理结果。

关键词：多动词处理动词连见规则形式化概念层次网络

A new multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth

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Chinese Journal of Aeronautics 2025年第1期38卷 568-585页

作者： Xinghui HAN Yanhui WANG Lin HUA Wuhao ZHUANG Fangyan ZHENG wei feng Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000China

Spiral bevel gears are critical transmission components,and are widely used in the aerospace *** paper proposes a new multi-DOF envelope forming process for fabricating spiral bevel ***,the multi-DOF envelope forming principle of spiral bevel gears is ***,the design methods for the envelope tool geometry and movement are proposed based on the envelope geometry and movement ***,the metal flow and tooth filling laws are revealed through 3D FE simulation of the multi-DOF envelope forming process of a typical spiral bevel ***,a new method for separating the envelope tool and the formed spiral bevel gear with back taper tooth is proposed to avoid their ***,experiments on multi-DOF envelope forming of this typical spiral bevel gear are conducted using new heavy load multi-DOF envelope forming *** simulation and experimental results show the feasibility of the proposed multi-DOF envelope forming process for fabricating spiral bevel gears with back taper tooth and the corresponding process design methods.

关键词： Multi-DOF envelope forming Spiral bevel gear Back taper tooth Metal flow Process design

When Software Security Meets Large Language Models:A Survey

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IEEE/CAA Journal of Automatica Sinica 2025年第2期12卷 317-334页

作者： Xiaogang Zhu wei Zhou Qing-Long Han Wanlun Ma Sheng Wen Yang xiang IEEE the School of Computer and Mathematical Sciences the University of Adelaide the School of Science Computing and Engineering Technologies Swinburne University of Technology

Software security poses substantial risks to our society because software has become part of our life. Numerous techniques have been proposed to resolve or mitigate the impact of software security issues. Among them, software testing and analysis are two of the critical methods, which significantly benefit from the advancements in deep learning technologies. Due to the successful use of deep learning in software security, recently,researchers have explored the potential of using large language models(LLMs) in this area. In this paper, we systematically review the results focusing on LLMs in software security. We analyze the topics of fuzzing, unit test, program repair, bug reproduction, data-driven bug detection, and bug triage. We deconstruct these techniques into several stages and analyze how LLMs can be used in the stages. We also discuss the future directions of using LLMs in software security, including the future directions for the existing use of LLMs and extensions from conventional deep learning research.

关键词： Large language models (LLMs) software analysis software security software testing

Constructing diverse switchable circularly polarized luminescence via a single azobenzene polymer film

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Chinese Chemical Letters 2025年第1期36卷 299-305页

作者： xiang Wang Qingping Song Zixiang He Gong Zhang Tengfei Miao Xiaoxiao Cheng wei Zhang State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Department of Polymer Science and EngineeringCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China School of Chemical and Environmental Engineering Anhui Polytechnic UniversityWuhu 241000China Jiangsu Key Laboratory for Chemistry of Low-Dimensional Materials School of Chemistry and Chemical EngineeringHuaiyin Normal UniversityHuaian 223300China

Recently circularly polarized luminescence(CPL)materials have attracted significant *** reversible dynamic property to these materials has been a key focus in cutting-edge fields,such as in high-level information ***,we provided a novel and general strategy involving handednessselective filtration and ground-state chiral self-recovery(CSR)in double film system to address this *** on this strategy,we achieved CPL switch through the reversible modulation of ground-state chirality including absorption and scattering circular dichroism(CD)signals over the full UV-visible wavelength range(365-700 nm)in a single azobenzene polymer(PAzo)*** importantly,by flexibly changing the type of fluorescent films,it is convenient to achieve general excited-state CSR,that is reversible switching of full-color including ideal white(CIE coordinate(0.33,0.33)),as well as room-temperature phosphorescent *** these CPL signals without almost any intensity decay after three cycles of onand-off *** results indicated that the trans-cis isomerization and ordered rearrangement of azobenzene units in PAzo film were the fundamental reasons for realizing CPL ***,based on this system we achieved dynamic visual encryption and decryption process including multiple decryption *** study provides an effective method for constructing a universally applicable chiroptical switch in excited state.

关键词： Circularly polarized luminescence Azobenzene polymer Multiple CPL Chiral switch Information encryption

Impact of temperature and salinity on fines detachment: AFM measurements and XDLVO theory

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Petroleum Science 2025年第1期22卷 338-347页

作者： wei-feng Yuan Yu-Long Yang Lu Yuan Ji-Rui Hou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum Unconventional Petroleum Research Institute China University of Petroleum

Fine particle detachment and subsequent migration can lead to severe pore plugging and consequent permeability decline. Therefore, it is crucial to quantify the critical condition when fine particle detachment occurs. The frequently observed deviations or even contradictions between experimental results and theoretical predictions of fines detachment arise from an insufficient understanding of adhesion force that can be highly influenced by salinity and temperature. To clarify the intrinsic influence of salinity and temperature on fines detachment, adhesion forces between carboxyl microspheres and hydrophilic silica substrates in an aqueous medium were measured at various salinities and temperatures using atomic force microscopy(AFM). The AFM-measured adhesion force decreases with increasing salinity or temperature. Trends of mean measured adhesion forces with temperature and salinity were compared with the DLVO and XDLVO theories. DLVO theory captured the trend with temperature via the impact of temperature on electric double layer interactions, whereas XDLVO theory captured the observed trend with salinity via the impact of salinity on the repulsive hydration force. Our results highlight the significance of hydration force in accurately predicting the fate of fines in porous media.

关键词： Adhesion force AFM Temperature Salinity XDLVO Hydration force

Glial cell line-derived neurotrophic factor improves impaired colonic motility in experimental colitis mice through connexin 43

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World Journal of Gastroenterology 2025年第8期31卷 82-95页

作者： wei Yang Rui Liu feng Xu Department of Gastroenterology The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Medical School Xiangyang Vocational and Technical CollegeXiangyang 441021Hubei ProvinceChina

BACKGROUND Colonic motility dysfunction is a common symptom of ulcerative colitis(UC),significantly affecting patients’quality of *** suggests that glial cell line-derived neurotrophic factor(GDNF)plays a role in restoring colonic *** To investigate whether GDNF enhances aberrant colonic motility in mice with experimental colitis via connexin 43(Cx43).METHODS An experimental colitis model was induced in male C57BL/6 mice using dextran sodium sulfate(DSS).The measurement of colonic transit time was conducted,and colon tissues were evaluated through transmission electron microscopy and hematoxylin and eosin *** mice were treated with exogenous GDNF and Gap 19,a selective Cx43 *** Cx43 and GDNF levels were detected via immunofluorescence,immunohistochemistry,and real-time polymerase chain *** levels of inflammatory markers,including interleukin-1β,tumor necrosis factor-α,interleukin-6,and C-reactive protein,were quantified using enzyme-linked immunosorbent *** Experimental colitis was successfully induced using DSS,and the findings exhibited that the colonic transit time was significantly delayed in colitis mice relative to the UC group(P<0.01).GDNF treatment improved colonic transit time and alleviated intestinal inflammation in DSS-induced colitis mice(P<0.05).In the UC+Gap19+GDNF group,colitis symptoms,colonic transit time,and inflammatory marker levels remained comparable to those in the UC group,indicating that the therapeutic effects of GDNF in UC mice were blocked by Gap *** GDNF improves colonic motility in mice with experimental colitis through a partially Cx43-mediated *** holds promise as a therapeutic option for improving colonic motility in patients with colitis.

关键词： Glial cell line-derived neurotrophic factor Ulcerative colitis Colonic motility Connexin 43 Dextran sodium sulfate model

Tetraphenylethylene-derived organic cages with persistent photogenic radicaloids and efficient photothermal conversion

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Science China Chemistry 2025年第2期68卷 661-669页

作者： Suqiong Yan Bo Yang Fanda feng Yuan Zhang Shirong Ban Hui Ma wei Huang State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China Shenzhen Research Institute of Nanjing University Shenzhen 518057China

Transformation of the electronic spin states has received significant interest in recent years because of its applications in the magnetic information storage materials and optical response ***,it can be formidably challenging to use ultraviolet(UV)light as a contactless stimulus to alter the electronic spin states of the supramolecular *** by the approach on the radical cation mechanism of the Scholl reaction and the photocyclization reactivity of tetraphenylethylene(TPE)derivatives,we report two photochromic cages(cage-TPE-1 and cage-TPE-2)that can be photochemically transformed from electron paramagnetic resonance(EPR)-silent to EPR-active form via UV irradiation due to the photo-induced electron transfer process at the TPE *** provided a strong single-electron signal with a g value of 2.003 in cage-TPE-1 and cage-TPE-2 but no signal was detected for the pristine samples without the *** transformation can be monitored by ultraviolet–visible–near-infrared(UV–vis–NIR)and photoluminescence(PL)*** photogenic radical cage intermediate was unstable in solution resulting in the degradation and intramolecular cyclization of the reactive species,while the radicals were found to be stable and persistent in the solid state due to the spin delocalization,the steric protection of confined cavities,and the oxygen *** theoretical calculations and spectral measurements suggest that the photogenic radical cage-TPE-2(•+)experiences photocyclization on the TPE *** with the close-shell cage,the radical cage-TPE-1(•+)and cage-TPE-2(•+)exhibit better photothermal conversion performance due to the incubated infrared absorption from open-shell electron feature and reduced band gap.

关键词： supramolecular cage photogenic radical photocyclization photothermal conversion