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Chinese Chemical Letters 2009年第6期20卷 660-662页

作者： Ping Zhang lan Zhi Wang Hui Shu Wu jia ming lan Yuan Li Yong Xiang Wang The College of Chemistry & Material Science Hebei Normal University Shijiazhuang 050016 China Department of Pathogenic Biology Hebei Medical University Shijiazhuang 050017 China

A series of novel 1,5-benzothiazepine derivatives containing COOC2H5/COONa groups at the C（2）-position were synthesized and evaluated for their antifungal and antibacterial activities by both disc diffusion and minimal inhibition concentration （MIC） methods. Most of the compounds have been shown to have moderate to good antibacterial activity against S. aureus, S. epidermidis and excellent antifungal activity against C. albicans.

关键词： 1,5-Benzothiazepine Antifungal Antibacterial activities

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Anchoring 1T-MoS_(2)petals on N-doped reduced graphene oxide for exceptional electromagnetic wave absorption

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 619-630页

作者： jia Zhao Haoran Lai ming Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou 121013China Yangtze Delta Region Institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 313001China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

The effective construction of electromagnetic(EM)wave absorption materials with thin matching thickness,broad bandwidth,and remarkable absorption is a great solution to EM pollution,which is a hot topic in current environmental *** this study,N-doped reduced graphene oxide(N-rGO)was first prepared using a facile hydrothermal ***,high-purity 1T-MoS_(2)petals were homogeneously anchored to the wrinkled surface of N-rGO to fabricate 1T-MoS_(2)@N-rGO *** numerous electric di-poles and profuse heterointerfaces in 1T-MoS_(2)@N-rGO would induced the multiple reflection and scattering of EM waves in a distinct-ive multidimensional structure formed by two-dimensional N-rGO and 1T-MoS_(2)microspheres with plentiful thin nanosheets,remarkable conduction loss derived from the migration of massive electrons in a well-constructed conductive network formed by 1T-MoS_(2)@N-rGO,and abundant polarization loss(including dipolar polarization loss and interfacial polarization loss).All of these gave the 1T-MoS_(2)@N-rGO nanocomposites superior EM wave absorption *** effective absorption bandwidth of 1T-MoS_(2)@N-rGO reached 6.48 GHz with a relatively thin matching thickness of 1.84 mm,and a minimum reflection loss of-52.24 dB was achieved at 3.84 ***,the radar scattering cross-section reduction value of 1T-MoS_(2)@N-rGO was up to 35.42 dB·m^(2) at 0°,which further verified the huge potential of our fabricated 1T-MoS_(2)@N-rGO nanocomposites in practical applications.

关键词： 1T-MoS_(2)@N-rGO nanocomposites conduction loss polarization loss ultrathin matching thickness electromagnetic wave absorption

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Alpha-decay properties of nuclei around neutron magic numbers

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Nuclear Science and Techniques 2025年第1期36卷 140-149页

作者： ming Li Chu-Xin Chen lan-Fang Xiao Yi Zhang Song Luo Xiao-Hua Li School of Nuclear Science and Technology University of South ChinaHengyang 421001China PET‑CT Center Chenzhou First People’s HospitalChenzhou 423000China Hengyang Ecological Environment Monitor Center Hengyang 421001China China Certification and Inspection Group Hefei 230000China National Exemplary Base for International Science and Technology Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

By combining experimental α-decay energies and half-lives, the α-particle preformation factor for nuclei around neutron magic numbers N of 126, 152, and 162 were extracted using the two-potential approach. The nuclei around the shell closure were more tightly bound than adjacent nuclei. Additionally, based on the WS4 mass model (Wang et al., Phys. Lett.B 734, 215 (2014)), we extended the two-potential approach to predict the α-decay half-lives of nuclei around N values of178 and 184 with Z of 119 and 120. We believe that our findings will serve as guidelines for future experimental studies.

关键词： adecay Preformation factor Neutron magic number Heavy and superheavy nuclei

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High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-ming Wu Lin He Lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Adsorption and retention of fracturing fluid and its impact on gas transport in tight sandstone with different clay minerals

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Petroleum Science 2025年第1期22卷 370-383页

作者： Yi-Jun Wang Li-Jun You jian Yang Yi-Li Kang ming-Jun Chen jia-jia Bai jian Tian State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Engineering Technology Research Institute of Southwest Oil & Gas Field Company PetroChina School of Petroleum Engineering Changzhou University State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University

To elucidate the adsorption characteristics and retention mechanisms of fracturing fluids in diverse clay minerals, we conducted on-line nuclear magnetic resonance(NMR) and atomic force microscopy(AFM)experiments. The depth and extent of solid phase damage are determined by the ratio between the size of fine fractions in fracturing fluid residue and the pore-throat size in experiments. Poor physical properties(K 0.5 m D) combined with a scattered distribution of retained fracturing fluid is associated with high gas phase recovery permeability, whereas a continuous sheet-like distribution results in low recovery permeability. The expansive surface area and presence of filamentous illite minerals facilitate the multiple winding and adsorption of fracturing fluids, demonstrating strong hydrogen-bonding, multi-layering and multiple adsorption properties. The geological characteristics of the main gas formations exhibit significant variation, and the severity of damage caused by fracturing fluids occurs in diverse sequences. To address this issue, a differentiated strategy for optimizing fracturing fluids has been proposed.

关键词： Clay minerals Formation damage Fracturing fluid retention distribution Adsorption morphology

Optimizing cooling approach of spiral coil for an electromagnetic steel teeming system of ladle in continuous casting production

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Journal of Iron and Steel Research International 2025年第1期32卷 85-94页

作者： ming He Qing-wei Wang Li-jia Zhao Wang-zhong Mu Xing-an Liu Qiang Wang College of Horticulture Shenyang Agricultural UniversityShenyang110866LiaoningChina Key Laboratory of Electromagnetic Processing of Materials(Ministry of Education) Northeastern UniversityShenyang110819LiaoningChina Key Laboratory of Protected Horticulture(Ministry of Education) Shenyang Agricultural UniversityShenyang110866LiaoningChina Department of Materials Science and Engineering KTH Royal Institute of TechnologyStockholm10044Sweden

To address the current issues with the conventional slide gate system utilized in the steel teeming process,a unique electromagnetic induction controlled automated steel teeming(EICAST)technology has been *** means of spiral coil in this technology is directly related to its service ***,heat transfer processes of air cooling and spray cooling were compared and ***,the impacts of water temperature,water flow rate and air flow rate were examined in order to maximize the spray cooling *** maintain coil temperature at a low value consistently throughout the entire thermal cycle process of the ladle,a combined cooling mode was finally *** simulation was applied to examine the coil temperature variation with different cooling systems and *** coil operation,spray cooling is said to be more *** controlling the water flow rate and air flow rate,the spray cooling effect is ***,water temperature has little or no impact when using spray *** cooling during the secondary refining process and spray cooling prior to coil operation are combined to further lower coil *** the direction of the spray cooling is from bottom to top,the coil temperature is lowered below 165℃.A practical induction coil cooling plan was provided for the EICAST technology’s production process.

关键词： Electromagnetic induction controlled automated steel teeming technology Spiral coil Spray cooling Heat transfer Continuous casting

Controlling segregation and hardenability of gear steel based on as-cast structure

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Journal of Iron and Steel Research International 2025年第1期32卷 144-158页

作者： Hai-jie Wang Ze Zhang Peng lan Gang Chen Pu Wang Chuan-hui jiang jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Weifang Iron and Steel Group Co. Ltd.Weifang 261000ShandongChina

Hardenability significantly impacts the distortion of gear during heat treatment,correlated to the uniformity of solute distribution in steel *** experimental analysis was conducted on the macrostructure,solute distribution,dendrite structure,and rod hardenability of 20CrMnTiH gear steel in continuously cast blooms and hot roller *** evaluation approach by the standards for the hardenability of gear steel rods and the corresponding blooms was analyzed,and the inheritance mechanism from solidification segregation to hardenability fluctuation of gear steel was *** results indicate that semi-macroscopic spot segregation located in the equiaxed zone exhibits larger size,higher solute enrichment,and worse solute homogeneity,leading to significant solute fluctuations in the blooms and hardenability fluctuation in the *** increasing the liquid steel superheat from 35 to 40℃,reducing the mold electromagnetic stirring from 300 to 100 A,and implementing the soft reduction(SR)of 7 mm at the solidification end,the equiaxed ratio of the strand decreased from 26.42%to 6.69%.Consequently,the solute fluctuation range and standard deviation decrease significantly in the transverse section,while the maximum segregation ratio,average fluctuation range,and average standard deviation of solutes C,Cr,and Mn in the spot segregation decrease at the same *** the meanwhile,the equiaxed ratio of the rod decreased from 24.89%to 4.09%,and the structure of the hardenability detection zone was transformed from equiaxed crystals to columnar ***,the solute fluctuation range and standard deviation in the transverse section decreased,while the homogeneity in spot segregation was also *** hardness difference of A and B surfaces at J9 and J15 positions was smaller than 2 HRC,meeting the qualification standard for hardenability.

关键词： Gear steel Continuous casting Solute distribution Dendritic structure Hardenability

Flotation separation of chalcopyrite from pyrite using mineral fulvic acid as selective depressant under weakly alkaline conditions

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中国有色金属学报 2025年第1期35卷 313-325页

作者： Zhi-hao SHEN Shu-ming WEN jia-mei HAO Qi-cheng FENG State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Land Resource EngineeringKunming University of Science and TechnologyKunming 650093China

Mineral fulvic acid(MFA)was used as an eco-friendly pyrite depressant to recover chalcopyrite by flotation with the use of the butyl xanthate as a *** experiments showed that MFA produced a stronger inhibition effect on pyrite than on *** separation of chalcopyrite from pyrite was realized by introducing 150 mg/L MFA at a pulp pH of approximately *** copper grade,copper recovery,and separation efficiency were 28.03%,84.79%,and 71.66%,*** adsorption tests,zeta potential determinations,and localized electrochemical impedance spectroscopy tests showed that more MFA adsorbed on pyrite than on chalcopyrite,which weakened the subsequent interactions between pyrite and the *** force microscope imaging further confirmed the adsorption of MFA on pyrite,and X-ray photoelectron spectroscopy results indicated that hydrophilic Fe-based species on the pyrite surfaces increased after exposure of pyrite to MFA,thereby decreasing the floatability of pyrite.

关键词： mineral fulvic acid chalcopyrite pyrite flotation separation

Homogeneous catalysis and heterogeneous separation: Ionic liquids as recyclable photocatalysts for hydroacylation of olefins

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Chinese Chemical Letters 2025年第2期36卷 417-421页

作者： Hao-Cong Li ming Zhang Qiyan Lv Kai Sun Xiao-lan Chen Lingbo Qu Bing Yu College of Chemistry School of Life Sciences Zhengzhou University

The photoinduced ligand-to-metal charge transfer （LMCT） process has been extensively investigated,however,the recovery of photocatalysts has remained a persistent challenge in the *** light of this issue,a novel approach involving the development of iron-based ionic liquids as photocatalysts has been pursued for the first time,with the goal of simultaneously facilitating the LMCT process and addressing the issue of photocatalyst ***,the iron-based ionic liquid 1–butyl–3-methylimidazolium tetrachloroferrate （C4mim-Fe Cl4） demonstrates exceptional recyclability and stability for the photocatalytic hydroacylation of *** study will pave the way for new approaches to photocatalytic organic synthesis using ionic liquids as recyclable photocatalysts.

关键词： Heterogeneous separation Homogeneous catalysis Ionic liquids LMCT Recyclable photocatalysts

Factors influencing vaginal cuff dehiscence after laparoscopic hysterectomy and the psychological state of the patients

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World Journal of Psychiatry 2025年第2期15卷 69-75页

作者： lan-Ying Wang Qi-Qin Wang jia-Nan Xu Si-Yuan Wang Yao Shi Department of Gynecology and Obstetrics Yuyao People’s HospitalYuyao 315400Zhejiang ProvinceChina

BACKGROUND Despite laparoscopic total hysterectomy provided more benefits to patients and has become one of the most commonly used surgical methods for total ***,vaginal cuff dehiscence is a serious complication after laparoscopic total hysterectomy and so far,there are limited studies on vaginal cuff dehiscence after a total *** To investigate the factors influencing vaginal cuff dehiscence after laparoscopic hysterectomy and the psychological state of the *** This study retrospectively,univariately,and multivariately analyzed the clinical data of patients who experienced vaginal cuff dehiscence after laparoscopic hysterectomy in Yuyao People’s Hospital from January 2015 to December *** regression was utilized to analyze the high-risk factors of vaginal cuff *** Among 1459 cases with laparoscopic hysterectomy,9 reported vaginal cuff dehiscence postoperatively,with an incidence of 0.617%.Univariate logistic regression analysis revealed that preoperative hemoglobin value[odds ratio(OR)=5.12,P=0.016],vaginal cuff suture method(OR=0.26,P=0.048),and postoperative first sexual lifetime(OR=15.86,P=0.002)were associated with vaginal cuff dehiscence following laparoscopic *** logistic regression analysis revealed that preoperative hemoglobin value of<90 g/L(OR=5.17,P=0.015)and time interval between postoperative first sexual life and operation of<3 months(OR=54.00,P=0.004)are independent risk factors for vaginal cuff dehiscence after laparoscopic *** Postoperative hemoglobin and the time interval between postoperative first sexual life and operation were the independent factors of developing vaginal cuff dehiscence after laparoscopic hysterectomy.

关键词： Laparoscopy Hysterectomy Vaginal cuff dehiscence Hemoglobin value First sex time