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Nano Research 2024年第7期17卷 5914-5921页

作者： chun-Ying chen Qi-Jie Mo Fu-Zhen Li Hai-Li Song Li Zhang MOE Laboratory of Bioinorganic and Synthetic Chemistry Lehn Institute of Functional MaterialsSchool of ChemistrySun Yat-Sen UniversityGuangzhou 510006China

Alkene hydrosilylation is one of the most concise and atom-economical methods to synthesize organosilicon ***,we reported the precise immobilization of metal single atoms(M-SAs;M=Ru,Rh,Ir,Pd,Pt,and Au)into a porphyrinic metalorganic framework(MOF)of PCN-222(PCN=porous coordination network),and then applied the resultant MOF composites of M-SAs@PCN-222 to alkene *** solvent-free conditions,Pt-SAs@PCN-222 displayed an especially high catalytic efficiency with the turnover frequency up to 119 s−1 and the maximum turnover number of 906,250 at room *** and theoretical studies revealed that there existed strong interactions between Pt-SAs@PCN-222 and the substrates,which helped to condense the substrates in the cavities of the porous *** density functional theory calculations and molecular dynamics simulations disclosed that PCN-222 could transfer electrons to Pt-SAs to enhance the silane oxidative addition and drive the reaction to proceed smoothly via Chalk–Harrod pathway.

关键词： alkene hydrosilylation single atom catalysts metal-organic frameworks precision chemistry synergistic catalysis

The influence of yttrium and manganese additions on the degradation and biocompatibility of magnesium-zinc-based alloys:In vitro and in vivo studies

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Journal of Magnesium and Alloys 2024年第2期12卷 608-624页

作者： Lei Shi Yang Yan chun-sheng Shao Kun Yu Bo Zhang Liang-jian chen Third Xiangya Hospital Central South UniversityChangsha 410013China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China School of Materials Science and Engineering Central South UniversityChangsha 410083China Department of Mechanical Engineering City University of Hong KongHong KongChina

The repair and regeneration of bone defects are highly challenging orthopedic ***,Mg-based implants have gained popularity due to their unique biodegradation and elastic modulus similar to that of human *** aim of our study is to develop a magnesium alloy with a controllable degradation that can closely match bone tissue to help injuries heal in vivo and avoid cytotoxicity caused by a sudden increase in ion *** this study,we prepared and modified Mg-3Zn,Mg-3Zn-1Y,and Mg-2Zn-1Mn by hot extrusion,and used Mg-2.5Y-2.5Nd was as a *** then investigated the effect of additions of Y and Mn on alloys'*** results show that Mn and Y can improve not only compression strength but also corrosion *** alloy Mg-2Zn-1Mn demonstrated good cytocompatibility in vitro,and for this reason we selected it for implantation in *** degraded Mg-2Zn-1Mn implanted a bone defect area did not cause obvious rejection and inflammatory reaction,and the degradation products left no signs of damage to the heart,liver,kidney,or ***,we find that Mg-2Zn-1Mn can promote an osteoinductive response in vivo and the formation of bone regeneration.

关键词： Magnesium alloy Biodegradation Biocompatibility Bone regeneration Bone defect repair

Prediction model on hydrolysis kinetics of phthalate monoester:A density functional theory study

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Journal of Environmental Sciences 2024年第1期135卷 51-58页

作者： Tong Xu Jingwen chen Deming Xia Weihao Tang Jiansheng Cui chun Liu Shuangjiang Li College of Environmental Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050000China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China

As primary degradation products of phthalate esters,phthalate monoesters(MPEs)have been widely detected in various aquatic environments and drawn growing toxicological *** kinetics that is of importance for assessing environmental persistence of chemicals remain elusive for ***,kinetics of base-catalyzed and neutral hydrolysis for 18 MPEs with different leaving groups was investigated by density functional theory *** indicate that MPEs with leaving groups having p Kaof<10 prefer dissociative transition *** are more persistent than their parents,and their hydrolysis half-lives were calculated to vary from 3.4 min to 79.2 years(p H=7–9).A quantitative structure-activity relationship model was developed for predicting the hydrolysis kinetics *** was found that p Kaof the leaving groups and electronegativity of the MPEs are key factors determining the hydrolysis *** work may lay a theoretical foundation for better understanding the chemical process that governs MPE persistence in aquatic environments.

关键词： Phthalate monoesters Phthalate esters Hydrolysis Density functional theory Quantitative structure-activity relationship

RB-DEM Modeling and Simulation of Non-Persisting Rough Open Joints Based on the IFS-Enhanced Method

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 337-359页

作者： Hangtian Song Xudong chen chun Zhu Qian Yin Wei Wang Qingxiang Meng Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Research Institute of Geotechnical Engineering Hohai UniversityNanjing210098China School of Earth Sciences and Engineering Hohai UniversityNanjing210098China State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyXuzhou221116China

When the geological environment of rock masses is disturbed,numerous non-persisting open joints can appear within *** is crucial to investigate the effect of open joints on the mechanical properties of rock ***,it has been challenging to generate realistic open joints in traditional experimental tests and numerical *** paper presents a novel solution to solve the *** utilizing the stochastic distribution of joints and an enhanced-fractal interpolation system(IFS)method,rough curves with any orientation can be *** Douglas-Peucker algorithm is then applied to simplify these curves by removing unnecessary points while preserving their fundamental ***,open joints are created by connecting points that move to both sides of rough curves based on the aperture *** modeling is performed to construct the final mesh ***,the RB-DEM method is applied to transform the mesh model into a discrete element model containing geometric information about these open ***,this study explores the impacts of rough open joint orientation,aperture,and number on rock fracture *** method provides a realistic and effective approach for modeling and simulating these non-persisting open joints.

关键词： Non-persisting rough open joints stochastic distribution of joints enhanced-IFS method RB-DEM

Combined strategies for improving the heterologous expression of a novel xylanase from Fusarium oxysporum Fo47 in Pichia pastoris

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Synthetic and Systems Biotechnology 2024年第3期9卷 426-435页

作者： chun Liu Yaping Zhang chunting Ye Fengguang Zhao Yian chen Shuangyan Han School of Biology and Biological Engineering South China University of TechnologyGuangzhou510640China School of Light Industry and Engineering South China University of TechnologyGuangzhou510640China

Xylanase,an enzyme capable of hydrolyzing non-starch polysaccharides found in grain structures like wheat,has been found to improve the organizational structure of dough and thus increase its *** our past work,one promising xylanase FXYL derived from Fusarium oxysporum Fo47 and first expressed 779.64 U/mL activity in *** has shown significant potential in improving the quality of whole wheat bread,making it become a candidate for development as a new flour *** optimization of expression elements and gene dose,the xylanase activity of FXYL strain carrying three-copies reached 4240.92 U/mL in *** addition,12 factors associated with the three stages of protein expression pathway were co-expressed individually in order in three-copies strain,and the translation factor Pab1 co-expression increased FXYL activity to 8893.53 U/***,combining the most effective or synergistic factors from three stages did not exhibit better results than co-expressing them *** further evaluate the industrial potential,the xylanase activity and protein concentration reached 81184.51 U/mL and 11.8 g/L in a 5 L fed-batch *** engineering strategies improved the expression of xylanase FXYL by more than 104-fold,providing valuable insights for the cost-effective industrial application of FXYL in the baking field.

关键词： Xylanase Pichia pastoris Heterologous protein Secretion expression

Effects of different moxibustion durations on lumbar disk herniation:a clinical study

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Frontiers of Nursing 2024年第1期11卷 47-56页

作者： Bin chen Ting Yang chun-Qin Zhu Department of Nursing Affiliated Hospital of Nanjing University of Chinese MedicineNanjingJiangsu 210004China

Objective:To explore the best duration of moxibustion on lumbar disk herniation(LDH).Methods:A total of 88 patients were randomly divided into control group and 15-min,30-min,and 45-min moxibustion *** control group was treated with conventional therapy,while the other 3 groups were intervened with different moxibustion *** back pain,dysfunction,lumbar function,and effective rates were evaluated before,in the first week and second week of ***:In low back pain,compared with the control group,the score of the 15-min group had no significant difference,but it was significantly lower in the 30-min and 45-min *** dysfunction and lumbar function,compared with the control group,the scores of the 15-min,30-min,and 45-min groups were significantly higher,and the scores of the 30-min and 45-min groups were significantly higher,but there was no significant difference between the 30-min and 45-min *** effective rates,there was no significant difference between the control group and 15-min group;the effective rates of the 30-min and 45-min groups were significantly higher than those of the control ***:Moxibustion has good therapeutic effect on LDH with specific moxibustion time.

关键词： duration of moxibustion lumbar disc herniation moxibustion

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

Remote sensing of air pollution incorporating integrated-path differential-absorption and coherent-Doppler lidar

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Defence Technology（防务技术） 2024年第1期31卷 594-601页

作者： Ze-hou Yang Yong chen chun-li chen Yong-ke Zhang Ji-hui Dong Tao Peng Xiao-feng Li Ding-fu Zhou School of Physics Beijing Institute of TechnologyBeijing 100081China Southwest Institute of Technical Physics Chengdu 610041SichuanChina School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China

An innovative complex lidar system deployed on an airborne rotorcraft platform for remote sensing of atmospheric pollution is proposed and *** system incorporates integrated-path differential absorption lidar(DIAL) and coherent-doppler lidar(CDL) techniques using a dual tunable TEA CO_(2)laser in the 9—11 μm band and a 1.55 μm fiber *** combining the principles of differential absorption detection and pulsed coherent detection,the system enables agile and remote sensing of atmospheric *** static tests validate the system’s real-time detection capabilities,including the measurement of concentration-path-length product(CL),front distance,and path wind speed of air pollution plumes over long distances exceeding 4 *** experiments is conducted with the *** of the pollutant concentration and the wind field is carried out in an approximately 1 km slant range over scanning angle ranges from 45°to 65°,with a radial resolution of 30 m and10 *** test results demonstrate the system’s ability to spatially map atmospheric pollution plumes and predict their motion and dispersion patterns,thereby ensuring the protection of public safety.

关键词： Differential absorption LIDAR Coherent Doppler lidar Remoting sensing Atmospheric pollution

Regulating metal-acid double site balance on mesoporous SiO2-Al2O3 composite oxide for supercritical n-decane cracking

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Petroleum Science 2024年第4期21卷 2881-2891页

作者： Liu-Ling chen Jun Zhang chun-Guang Li Li-Qun Fei Bo Wang chen-Qi Zhang Yi Jiao Jian-Li Wang Institute of New Energy and Low-Carbon Technology Sichuan University Engineering Research Center of Combustion and Cooling for Aerospace Power Ministry of Education School of Chemical Engineering Sichuan University State Key Laboratory of Industrial Vent Gas Reuse Southwest Institute of Chemical Co. Ltd Science and Technology on Scramjet Laboratory Beijing Power Machinery Research Institute

The balance between metal and acid sites directly affects the preparation of high-performance cracking catalysts with high heat sink and low ***,how to control acid-metal sites balance and its relationship with cracking performance are reported *** this work,a series of Pt/Al2O3-SiO2dual sites catalysts with different metal to acid active sites ratio(CM/CSA) were constructed by ethanolassisted impregnation method and the impact on n-decane cracking under supercritical conditions was systematically and deeply *** results showed that the conversion and carbon deposition increased gradually with varied CM/CSAand reached the balance at CM/CSAof *** proper ratio CM/CSA（0.13） can balance the deep dehydrogenation coking over metal active sites and high heat sink of cracking over acid active sites,the chemical heat sink reaches amazing 1.75 MJ/kg and carbon deposition is only22.03 mg/cm2at 750℃.Meanwhile,the few metal sites at low CM/CSAand the few strong acid sites at high CM/CSAare the main factors limiting the cracking *** CM/CSAlimit the activation of C-H bond and deep dehydrogenation of coking precursor,resulting in relative low cracking activity and carbon deposition,while high CM/CSAlimit the activation of C-C bond and increase the deep *** this contribution,design and construction of metal-acid dual sites can not only provide the technical solution for the preparation of high heat sink and low coking cracking catalyst,but also deepen the understanding of the cracking path of hydrocarbon fuel.

关键词： Metal-acid dual sites balance Catalytic cracking Hydrocarbon fuels Chemical heat sink Carbon deposition

Energy saving analysis for CO_(2)–O_(2)mixed injection technology in converter steelmaking

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Journal of Iron and Steel Research International 2024年第5期31卷 1095-1103页

作者： Bao-chen Han chun-liang Gao Ya-qiang Li Dan Liu Guang-sheng Wei Rong Zhu Hebei Key Laboratory of Material Near-Net Forming Technology School of Material Science and EngineeringHebei University of Science and TechnologyShijiazhuang050018HebeiChina Department of Automotive Engineering Hebei Vocational University of Technology and EngineeringXingtai054000HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

Energy-saving in China's iron and steel industry still relies on the development and improvement of short-term energy saving ***,a special converter smelting technology incorporating energy saving was *** evaluate the energy-saving potential of the CO_(2)–O_(2)mixed injection(COMI)technology,collected production data were used to develop an improved techno-economic *** reveal that the technology can save energy through auxiliary material consumption,sensible heat of solid by-product,iron loss reduction,and energy *** application of COMI technology in an enterprise is cost effective,involving the energy saving potential of 0.206 GJ/t,the cost of conserved energy of−48.83 yuan/GJ,and a simple payback period of 0.35 year for a 60-million-yuan *** analysis shows that the investment cost and discount rate primarily influence the cost of conserved energy of the *** the discount rate increased,the cost of conserved energy also gradually ***,the COMI technology is an energy-saving technology with good development prospects.

关键词： Converter steelmaking COMI technology Energy saving Techno-economic model Investment cost