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Robotic vs laparoscopic abdominoperineal resection for rectal cancer:A propensity score matching cohort study and metaanalysis
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作者 Li Song Wen-Qiong Xu +1 位作者 Zheng-Qiang Wei gang tang 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第5期1280-1290,共11页
BACKGROUND Robotic surgery(RS)is gaining popularity;however,evidence for abdominoperineal resection(APR)of rectal cancer(RC)is scarce.AIM To compare the efficacy of RS and laparoscopic surgery(LS)in APR for RC.METHODS... BACKGROUND Robotic surgery(RS)is gaining popularity;however,evidence for abdominoperineal resection(APR)of rectal cancer(RC)is scarce.AIM To compare the efficacy of RS and laparoscopic surgery(LS)in APR for RC.METHODS We retrospectively identified patients with RC who underwent APR by RS or LS from April 2016 to June 2022.Data regarding short-term surgical outcomes were compared between the two groups.To reduce the effect of potential confounding factors,propensity score matching was used,with a 1:1 ratio between the RS and LS groups.A meta-analysis of seven trials was performed to compare the efficacy of robotic and laparoscopic APR for RC surgery.RESULTS Of 133 patients,after propensity score matching,there were 42 patients in each group.The postoperative complication rate was significantly lower in the RS group(17/42,40.5%)than in the LS group(27/42,64.3%)(P=0.029).There wasno significant difference in operative time(P=0.564),intraoperative transfusion(P=0.314),reoperation rate(P=0.314),lymph nodes harvested(P=0.309),or circumferential resection margin(CRM)positive rate(P=0.314)between the two groups.The meta-analysis showed patients in the RS group had fewer positive CRMs(P=0.04),lesser estimated blood loss(P<0.00001),shorter postoperative hospital stays(P=0.02),and fewer postoperative complications(P=0.002)than patients in the LS group.CONCLUSION Our study shows that RS is a safe and effective approach for APR in RC and offers better short-term outcomes than LS. 展开更多
关键词 Robotic surgery Laparoscopic surgery Abdominoperineal resection Postoperative complications Propensity score
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Pressure-dependent electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X=Ca,Mg):A first-principles study
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作者 Chunbao Feng Changhe Wu +8 位作者 Xin Luo Tao Hu Fanchuan Chen Shichang Li Shengnan Duan Wenjie Hou Dengfeng Li gang tang gang Zhang 《Journal of Semiconductors》 EI CAS CSCD 2023年第10期52-60,共9页
Hydrostatic pressure provides an efficient way to tune and optimize the properties of solid materials without chang-ing their composition.In this work,we investigate the electronic,optical,and mechanical properties of... Hydrostatic pressure provides an efficient way to tune and optimize the properties of solid materials without chang-ing their composition.In this work,we investigate the electronic,optical,and mechanical properties of antiperovskite X_(3)NP(X^(2+)=Ca,Mg)upon compression by first-principles calculations.Our results reveal that the system is anisotropic,and the lat-tice constant a of X_(3)NP exhibits the fastest rate of decrease upon compression among the three directions,which is different from the typical Pnma phase of halide and chalcogenide perovskites.Meanwhile,Ca_(3)NP has higher compressibility than Mg_(3)NP due to its small bulk modulus.The electronic and optical properties of Mg_(3)NP show small fluctuations upon compression,but those of Ca_(3)NP are more sensitive to pressure due to its higher compressibility and lower unoccupied 3d orbital energy.For example,the band gap,lattice dielectric constant,and exciton binding energy of Ca_(3)NP decrease rapidly as the pressure increases.In addition,the increase in pressure significantly improves the optical absorption and theoretical conversion effi-ciency of Ca_(3)NP.Finally,the mechanical properties of X_(3)NP are also increased upon compression due to the reduction in bond length,while inducing a brittle-to-ductile transition.Our research provides theoretical guidance and insights for future experi-mental tuning of the physical properties of antiperovskite semiconductors by pressure. 展开更多
关键词 ANTIPEROVSKITE hydrostatic pressure physical properties first-principles calculations
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A low-cost green approach for synthesis of lead oxide from waste lead ash for use in new lead-acid batteries 被引量:2
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作者 Wei Zhang gang tang +4 位作者 Xiaoqin Xiang Renyu Wang Shuangquan Gao Xinfeng Zhu Qiting Zuo 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第7期1674-1679,共6页
This paper proposes a novel method relating to the recycling of waste lead ash originated from procedure of lead alloy production.The spent lead ash was first disposed by acetic acid leaching system,where lead ash str... This paper proposes a novel method relating to the recycling of waste lead ash originated from procedure of lead alloy production.The spent lead ash was first disposed by acetic acid leaching system,where lead ash structure wrapping impurities would be destroyed.The synthesis of lead oxide products was conducted at a lower temperature of 90℃.The effect of molar ratio of CH3 COOH to lead content of the ash on leaching efficiency was studied through the acetic acid leaching system.The results demonstrate that 84.6%of lead could be obtained in the leaching solution,while merely 0.7%of Fe blend in solution within a leaching time of 120 min.In the stage of lead oxide synthesis from leaching solution,the yield of lead oxide products could reach up to 94.4%when the molar ratio of NaOH to lead in filtrate was 2.5.This novel green method could shed light on the reuse of lead from exhausted ash with a much more convenient and environmentally friendly procedure. 展开更多
关键词 WASTE LEAD ASH LEACHING Acetic acid Solution synthesis LEAD OXIDE products
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Left bundle branch pacing with optimization of cardiac resynchronization treatment:A case report 被引量:2
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作者 Deng-Hong Zhang Ming-Jian Lang +2 位作者 gang tang Xiao-Xiao Chen Hong-Fei Li 《World Journal of Clinical Cases》 SCIE 2020年第18期4266-4271,共6页
BACKGROUND Cardiac resynchronization therapy(CRT)is a well-established therapy for patients with cardiomyopathy.CASE SUMMARY The patient underwent left bundle branch area and left ventricular(reaching the left ventric... BACKGROUND Cardiac resynchronization therapy(CRT)is a well-established therapy for patients with cardiomyopathy.CASE SUMMARY The patient underwent left bundle branch area and left ventricular(reaching the left ventricular lateral vein through the coronary sinus)pacing.The optimal CRT was performed under the right bundle branch of the patient by adjusting the optimal a-v and v-v interphases to achieve the maximal benefit of the treatment.CONCLUSION The patient was diagnosed with left bundle branch block and heart failure.A left bundle branch area pacemaker assisted in correcting the complete left bundle branch block.However,the shorter QRS wave shape after pacemaker implantation through the left bundle branch area indicated a complete right bundle branch block pattern.Hence,the left bundle branch area pacemaker is not always considered as the optimal treatment.The left bundle branch pacing with the optimization of cardiac resynchronization treatment may serve as a new CRT strategy. 展开更多
关键词 Cardiac resynchronization therapy CARDIOMYOPATHY Left bundle branch Case report
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Bio-Based Trivalent Phytate:A Novel Strategy for Enhancing Fire Performance of Rigid Polyurethane Foam Composites 被引量:1
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作者 Bing Zhang Sujie Yang +4 位作者 Mengru Liu Panyue Wen Xiuyu Liu gang tang Xiangrong Xu 《Journal of Renewable Materials》 SCIE EI 2022年第5期1201-1220,共20页
Biomass phytic acid has potential flame retardant value as the main form of phosphorus in plant seeds.In this study,phytate-based flame retardants aluminum phytate(PA-Al)and iron phytate(PA-Fe)were synthesized and cha... Biomass phytic acid has potential flame retardant value as the main form of phosphorus in plant seeds.In this study,phytate-based flame retardants aluminum phytate(PA-Al)and iron phytate(PA-Fe)were synthesized and characterized.Subsequently,they were introduced into rigid polyurethane foam(RPUF)as flame retardants by one-step water-blown method.The results indicated that RPUF/PA-Fe30 exhibited the highest char residue of 22.1 wt%,significantly higher than 12.4 wt%of RPUF.Cone calorimetry analysis showed that the total heat release(THR)of RPUF/PA-Al30 decreased by 17.0%and total smoke release(TSR)decreased by 22.0%compared with pure RPUF,which were the lowest,demonstrating a low fire risk and good smoke suppression.Thermogravimetric analysis-Fourier transform infrared spectrometer(TG-FTIR)implied the release intensity of flammable gases(hydrocarbons,esters)and toxic gases(isocyanate,CO,aromatic compounds,HCN)of composites was significantly reduced after the addition of PA-Fe.The analysis of char residue indicated that the RPUF composites formed a dense char layer with a high degree of graphitization after the addition of PA-Al/PA-Fe,endowing RPUF composites with excellent mass&heat transmission inhibition effect and fire resistance in the combustion process. 展开更多
关键词 Bio-based flame retardant phytic acid salt rigid polyurethane foam COMPOSITES smoke&toxicity suppression
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Electrocaloric effect in ferroelectric materials:From phase field to first-principles based effective Hamiltonian modeling 被引量:1
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作者 Jingtong Zhang Xu Hou +2 位作者 Yajun Zhang gang tang Jie Wang 《Materials Reports(Energy)》 2021年第3期34-63,共30页
Electrocaloric effect(ECE)of ferroelectrics has attracted considerable interest due to its potential application in environmentally friendly solid-state refrigeration.The discovery of giant ECE in ferroelectric thin f... Electrocaloric effect(ECE)of ferroelectrics has attracted considerable interest due to its potential application in environmentally friendly solid-state refrigeration.The discovery of giant ECE in ferroelectric thin films has greatly renewed the research activities and significantly stimulated experimental and theoretical investigations.In this review,the recent progress on the theoretical modeling of ECE in ferroelectric and antiferroelectric materials are introduced,which mainly focuses on the phase field modeling and first-principles based effective Hamiltonian method.We firstly provide the theoretical foundation and technique details for each method.Then a comprehensive review on the progress in the application of two methods and the strategies to tune the ECE are presented.Finally,we outline the practical procedure on the development of multi-scale computational method without experiemtal parameters for the screening of optimized electrocaloric materials. 展开更多
关键词 Electrocaloric effect Ferroelectric materials Phase field simulation Machine learning models First-principles based effective HAMILTONIAN MODELING
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Mechanical Properties of Formamidinium Halide Perovskites FABX_3(FA=CH(NH_2)_2; B=Pb, Sn; X=Br, I) by First-Principles Calculations
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作者 Lei Guo gang tang Jiawang Hong 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第5期44-48,共5页
The mechanical properties of formamidinium halide perovskites FABX_3(FA=CH(NH_2)_2; B=Pb, Sn; X=Br, I)are systematically investigated using first-principles calculations. Our results reveal that FABX_3 perovskites pos... The mechanical properties of formamidinium halide perovskites FABX_3(FA=CH(NH_2)_2; B=Pb, Sn; X=Br, I)are systematically investigated using first-principles calculations. Our results reveal that FABX_3 perovskites possess excellent mechanical flexibility, ductility and strong anisotropy. We shows that the planar organic cation FA+ has an important effect on the mechanical properties of FABX3 perovskites. In addition, our results indicate that (i) the moduli(bulk modulus B, Young's modulus E, and shear modulus G) of FABBr_3 are larger than those of FABI_3 for the same B atom, and (ii) the moduli of FAPbX_3 are larger than those of FASnX_3 for the same halide atom. The reason for the two trends is demonstrated by carefully analyzing the bond strength between B and X atoms based on the projected crystal orbital Hamilton population method. 展开更多
关键词 FA=CH SN MECHANICAL Properties of Formamidinium HALIDE Perovskites FABX3 by First-Principles Calculations B FA CH
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Climatic Regionalization of Orange Osmanthus in Pucheng County Based on GIS
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作者 Da YING Hezhang CAI +3 位作者 Junliang ZHENG gang tang Dan LI 《Agricultural Biotechnology》 CAS 2020年第6期99-103,共5页
[Objectives]This study was conducted to scientifically plan orange osmanthus planting in Pucheng County to promote the development of agricultural economy.[Methods]Two factors,the total number of days with daily avera... [Objectives]This study was conducted to scientifically plan orange osmanthus planting in Pucheng County to promote the development of agricultural economy.[Methods]Two factors,the total number of days with daily average temperature≥15℃from March to August and the total number of days with daily average temperature≥20℃in September were determined as the regionalization index factors using the weather data and geographic information data of Pucheng County,according to the 80%guarantee rate principle,the mean square error method and the actual growth law of orange osmanthus.Then,according to the weighted stack method,comprehensively considering the on-site inspection results and expert opinions,the suitability of orange osmanthus planting layout in Pucheng County was evaluated,and the GIS spatial interpolation technology was applied to complete the refined agroclimatic regionalization.[Results]The growth of Pucheng orange osmanthus has a great relationship with the thermal conditions,and it is clear that the suitable,sub-suitable and unsuitable areas for orange osmanthus planting in Pucheng County have certain applicability and maneuverability.[Conclusions]This study will play a scientific guiding role in the industrialization and development of orange osmanthus planting in Pucheng County. 展开更多
关键词 Orange osmanthus GIS Index factor Suitability evaluation Climatic regionalization
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Combined Effect of Uniaxial Strain and Magnetic Field on the Exciton States in Semiconducting Single-Walled Carbon Nanotubes
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作者 Xin-Yue Zhang Gui-Li Yu +1 位作者 Li-Hua Wang gang tang 《Chinese Physics Letters》 SCIE CAS CSCD 2018年第8期66-69,共4页
The exciton states of semiconducting carbon nanotubes are calculated by a tight-binding model supplemented by Coulomb interactions under the combined effect of uniaxial strain and magnetic field. It is found that the ... The exciton states of semiconducting carbon nanotubes are calculated by a tight-binding model supplemented by Coulomb interactions under the combined effect of uniaxial strain and magnetic field. It is found that the excitation energies and absorption spectra of zigzag tubes(11,0) and(10,0) show opposite trends with the strain under the action of the magnetic field. For the(11,0) tube, the excitation energy decreases with the increasing uniaxial strain, with a splitting appearing in the absorption spectra. For the(10,0) tube, the variation trend firstly increases and then decreases, with a reversal point appearing in the absorption spectra. More interesting,at the reversal point the intensity of optical absorption is the largest because of the degeneracy of the two bands nearest to the Fermi Level, which is expected to be observed in the future experiment. The similar variation trend is also exhibited in the binding energy for the two kinds of semiconducting tubes. 展开更多
关键词 Combined Effect of Uniaxial Strain and Magnetic Field on the Exciton States in Semiconducting Single-Walled Carbon Nanotubes
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Facile low-temperature supercritical carbonization method to prepare high-loading nickel single atom catalysts for efficient photodegradation of tetracycline 被引量:1
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作者 Han Qiao Lirong Zheng +3 位作者 Shiwen Hu gang tang Hongri Suo Chongxuan Liu 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第4期373-384,共12页
Environmental photocatalysis is a promising technology for treating antibiotics in wastewater.In this study,a supercritical carbonization method was developed to synthesize a single-atom photocatalyst with a high load... Environmental photocatalysis is a promising technology for treating antibiotics in wastewater.In this study,a supercritical carbonization method was developed to synthesize a single-atom photocatalyst with a high loading of Ni(above 5 wt.%)anchored on a carbonnitrogen-silicate substrate for the efficient photodegradation of a ubiquitous environmental contaminant of tetracycline(TC).The photocatalyst was prepared from an easily obtained metal-biopolymer-inorganic supramolecular hydrogel,followed by supercritical drying and carbonization treatment.The low-temperature(300℃)supercritical ethanol treatment prevents the excessive structural degradation of hydrogel and greatly reduces the metal clustering and aggregation,which contributed to the high Ni loading.Atomic characterizations confirmed that Ni was present at isolated sites and stabilized by Ni-N and Ni-O bonds in a Ni-(N/O)_(6)-C/SiC configuration.A 5%Ni-C-Si catalyst,which performed the best among the studied catalysts,exhibited a wide visible light response with a narrow bandgap of 1.45 eV that could efficiently and repeatedly catalyze the oxidation of TC with a conversion rate of almost 100% within 40 min.The reactive species trapping experiments and electron spin resonance(ESR)tests demonstrated that the h+,and·O_(2)-were mainly responsible for TC degradation.The TC degradation mechanism and possible reaction pathways were provided also.Overall,this study proposed a novel strategy to synthesize a high metal loading singleatom photocatalyst that can efficiently remove TC with high concentrations,and this strategy might be extended for synthesis of other carbon-based single-atom catalysts with valuable properties. 展开更多
关键词 Carbon-based single-atom catalyst NICKEL Photocatalytic degradation TETRACYCLINE Visible light
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Breaking the symmetry of colloidal 2D nanoplatelets:Twist induced quantum coupling
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作者 Zahid Nazir Yingzhuo Lun +8 位作者 Jialu Li Gaoling Yang Mingrui Liu Shuqi Li gang tang Guofeng Zhang Jiawang Hong Liantuan Xiao Haizheng Zhong 《Nano Research》 SCIE EI CSCD 2023年第7期10522-10529,共8页
Twist provides a new degree of freedom for nanomaterial modifications,which can provide novel physical properties.Here,colloidal two-dimensional(2D)twisted CdSe nanoplatelets(NPLs)are successfully fabricated and their... Twist provides a new degree of freedom for nanomaterial modifications,which can provide novel physical properties.Here,colloidal two-dimensional(2D)twisted CdSe nanoplatelets(NPLs)are successfully fabricated and their morphology can change from totally flat to edge-twisted,and then to middle-twisted with prolonged reaction time.By combining experiments and corresponding theoretical analyses,we have established the length-dependent relationships between the surface energy and twist,with a critical lateral dimension of 30 nm.We found that the defects formed during the synthesis process play a vital role in generating intense stress that develops a strong torsion tensor around the edges,resulting in edge-twisted and final middletwisted NPLs.Furthermore,due to the geometric asymmetry of twisted NPLs,the dissymmetry factor of single particle NPLs can reach up to 0.334.Specifically,quantum coupling occurs in middle-twisted NPLs by twisting one parent NPL into two daughter NPLs,which are structurally and electronically coupled.This work not only further deepens our understanding of the twist mechanism of 2D NPLs during colloidal synthesis,but also opens a pathway for applications using twistronics and quantum technology. 展开更多
关键词 NANOPLATELETS CDSE TWIST circular dichroism quantum coupling
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Environmental Stability and Transmissibility of Enveloped Viruses at Varied Animate and Inanimate Interfaces
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作者 Li Zeng Junya Li +9 位作者 Meilin Lv Zikang Li Linlin Yao Jie Gao Qi Wu Ziniu Wang Xinyue Yang gang tang Guangbo Qu Guibin Jiang 《Environment & Health》 2023年第1期15-31,共17页
Enveloped viruses have been the leading causative agents of viral epidemics in the past decade,including the ongoing coronavirus disease 2019 outbreak.In epidemics caused by enveloped viruses,direct contact is a commo... Enveloped viruses have been the leading causative agents of viral epidemics in the past decade,including the ongoing coronavirus disease 2019 outbreak.In epidemics caused by enveloped viruses,direct contact is a common route of infection,while indirect transmissions through the environment also contribute to the spread of the disease,although their significance remains controversial.Bridging the knowledge gap regarding the influence of interfacial interactions on the persistence of enveloped viruses in the environment reveals the transmission mechanisms when the virus undergoes mutations and prevents excessive disinfection during viral epidemics.Herein,from the perspective of the driving force,partition efficiency,and viral survivability at interfaces,we summarize the viral and environmental characteristics that affect the environmental transmission of viruses.We expect to provide insights for virus detection,environmental surveillance,and disinfection to limit the spread of severe acute respiratory syndrome coronavirus 2. 展开更多
关键词 enveloped virus environmental transmission interface SURVIVABILITY SARS-CoV-2
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不同放置角度的建筑装饰材料PMMA的火焰蔓延特性 被引量:6
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作者 黄新杰 刘伟 +3 位作者 陈功建 王纯洁 唐刚 张浩 《过程工程学报》 CAS CSCD 北大核心 2018年第3期454-460,共7页
为揭示建筑装饰材料聚甲基丙烯酸甲酯(有机玻璃,PMMA)在不同放置角度下的火焰蔓延特性,通过自主搭建的小尺寸火焰蔓延实验平台,研究了宽3 cm、厚2 mm的PMMA试样在不同放置角度下的火焰蔓延特性.结果表明,放置角度对PMMA火焰蔓延过程... 为揭示建筑装饰材料聚甲基丙烯酸甲酯(有机玻璃,PMMA)在不同放置角度下的火焰蔓延特性,通过自主搭建的小尺寸火焰蔓延实验平台,研究了宽3 cm、厚2 mm的PMMA试样在不同放置角度下的火焰蔓延特性.结果表明,放置角度对PMMA火焰蔓延过程中热解区域及预热区长度影响很大,由15°到30°及由-60°到-75°时(顺流火焰蔓延时放置角度为正,逆流火焰蔓延时放置角度为负),平均火焰倾角增加幅度最大.顺流火焰蔓延的火焰长度随放置角度增加先略减小后逐渐增加,逆流火焰蔓延的火焰长度随放置角度的绝对值增加而略减小.放置角度由0°到15°时,顺流火焰蔓延的平均速度呈跃变增长,逆流火焰蔓延的平均速度随放置角度绝对值增加而略降低. 展开更多
关键词 有机玻璃 放置角度 顺流火焰蔓延 逆流火焰蔓延 火焰蔓延速度
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玻纤增强聚酰胺6/次磷酸钇复合材料的制备及其阻燃性能 被引量:2
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作者 唐刚 姜浩浩 +3 位作者 陈丽娟 张浩 刘纯林 周子健 《过程工程学报》 CAS CSCD 北大核心 2018年第6期1340-1346,共7页
以六水合氯化钇(YCl3·6H2O)和次磷酸钠(NaH2PO2)为原料,采用共沉淀法制备了一种新型稀土金属次磷酸盐-次磷酸钇(YHP),对其进行了表征;以YHP为阻燃剂,采用熔融共混法制备了系列玻纤增强聚酰胺6(GFPA)/次磷酸钇复合材料(GFPA/YHP),... 以六水合氯化钇(YCl3·6H2O)和次磷酸钠(NaH2PO2)为原料,采用共沉淀法制备了一种新型稀土金属次磷酸盐-次磷酸钇(YHP),对其进行了表征;以YHP为阻燃剂,采用熔融共混法制备了系列玻纤增强聚酰胺6(GFPA)/次磷酸钇复合材料(GFPA/YHP),采用热重、极限氧指数(LOI)、UL-94垂直燃烧和微型量热测试研究了YHP添加量对复合材料热稳定性、阻燃性能及燃烧性能的影响.结果表明,YHP已成功制备,其具有棒状结构,长度为20~100mm,宽度为5~20mm,热稳定性很高,降解温度T5%为410℃,最大热失重速率温度Tmax为412℃,750℃下热解的残炭率为90.8wt%.加入YHP降低了GFPA/YHP复合材料的热分解温度,但提高了其成炭率和高温稳定性,YHP添加量为20wt%时,复合材料的热分解温度为373℃,最大热失重速率温度为414℃,700℃下热解的残炭率为50.42wt%;YHP可有效提高复合材料的阻燃性能,极限氧指数(LOI)达27.5vol%,垂直燃烧级别达UL-94 V-1级;YHP可有效降低复合材料燃烧过程的热释放速率峰值(PHRR)和总放热(THR)量,二者分别降至327 W/g和15.8 kJ/g,比GFPA分别下降了14.1%和25.4%,表明YHP有效降低了GFPA/YHP复合材料燃烧的火灾危险性. 展开更多
关键词 次磷酸钇 聚酰胺6 复合材料 阻燃 热稳定性
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阻燃硬质聚氨酯泡沫塑料垂直火蔓延特性研究 被引量:3
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作者 黄新杰 王纯洁 +3 位作者 高金达 陈成 唐刚 王昌龙 《过程工程学报》 CAS CSCD 北大核心 2020年第7期843-851,共9页
通过一步合成法制备了阻燃硬质聚氨酯泡沫,自主搭建保温材料火蔓延实验台,采用中小尺寸实验对比研究了阻燃及非阻燃硬质聚氨酯的垂直火蔓延特性,分析了火焰结构特性、火蔓延速度、火焰温度、质量损失速率等参数的变化规律。结果表明,火... 通过一步合成法制备了阻燃硬质聚氨酯泡沫,自主搭建保温材料火蔓延实验台,采用中小尺寸实验对比研究了阻燃及非阻燃硬质聚氨酯的垂直火蔓延特性,分析了火焰结构特性、火蔓延速度、火焰温度、质量损失速率等参数的变化规律。结果表明,火蔓延过程中,材料表面均出现了炭化现象,垂直双面燃烧过程中聚氨酯纯样RPUF燃烧最剧烈,阻燃剂膨胀石墨(EG)、次磷酸铝(AHP)和二乙基次膦酸铝(ADP)的加入,抑制了材料的燃烧和蔓延,使材料燃烧的火蔓延速度、质量损失速率及温度等参数都相应降低。RPUF/AHP5垂直双面火蔓延过程中,火焰稳定性差,在20s后出现熄灭现象,原因是阻燃剂次磷酸铝(RPUF/AHP5)受热挥发出难燃气体。AHP降解后形成的含磷化合物可促进聚氨酯分子链成炭,导致产生熄灭现象。而RPUF/ADP5火蔓延过程中,同样出现了熄灭现象,其熄灭的程度低于阻燃剂次磷酸铝(RPUF/AHP5)试样。RPUF/EG5火蔓延过程中试样表面温度存在两个峰值,由于RPUF/EG5燃烧生成的炭层不稳定所致。当温度高于400℃时炭层被迅速氧化,热量穿透炭层使内部未燃样品热解,生成温度的第二个峰值。 展开更多
关键词 硬质聚氨酯 膨胀石墨 次磷酸铝 二乙基次膦酸铝 垂直火蔓延
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Enhanced piezo-response in copper halide perovskites based PVDF composite films 被引量:5
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作者 Sheng Huang gang tang +8 位作者 Hailong Huang Xian-gang Wu Puming Zhou Lin Zou Lei Xie Jianming Deng Xueyun Wang Haizheng Zhong Jiawang Hong 《Science Bulletin》 SCIE EI CSCD 2018年第19期1254-1259,共6页
ln-situ fabricated perovskite nanocrystals in polymeric matrix provide new generation composite mate- rials for plenty of cutting edge technology. In this work, we report the in-situ fabrication of copper halide perov... ln-situ fabricated perovskite nanocrystals in polymeric matrix provide new generation composite mate- rials for plenty of cutting edge technology. In this work, we report the in-situ fabrication of copper halide perovskite (MA_2CuCI_4, MA:CH_3NH+3) embedded poly(vinylidene fluoride) (PVDF) composite films. The optimized MA_2CuCI_4/PVDF composite films exhibit greatly enhanced piezo-response in comparasion with pure PVDF films. The enhancements were invesitgated and explained by applying piezo-response force microscopy (PFM) measurements and density functional theory (DFT) caculations. We proposed that the high piezoelectric properties of MA_2CuCI_4/PVDF composite films could be related to the large Cu off-centering displacement, the strong interactions between MA_2CuCI_4 and PVDF as well as large stress concentration around the MA_2CuCI_4 particles in the films. These piezoelectric composite films are expected to be suitable functional materials for flexible and/or wearable niezoelectrics. 展开更多
关键词 PEROVSKITE PIEZOELECTRIC Composite films MA_2CuCI_4
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A Wavelet-Based Method to Predict Muscle Forces From Surface Electromyography Signals in Weightlifting 被引量:3
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作者 Gaofeng Wei Feng Tian +1 位作者 gang tang Chengtao Wang 《Journal of Bionic Engineering》 SCIE EI CSCD 2012年第1期48-58,共11页
The purpose of this study was to develop a wavelet-based method to predict muscle forces from surface electromyography (EMG) signals in vivo. The weightlifting motor task was implemented as the case study. EMG signa... The purpose of this study was to develop a wavelet-based method to predict muscle forces from surface electromyography (EMG) signals in vivo. The weightlifting motor task was implemented as the case study. EMG signals of biceps brachii, triceps brachii and deltoid muscles were recorded when the subject carried out a standard weightlifting motor task. The wavelet-based algorithm was used to process raw EMG signals and extract features which could be input to the Hill-type muscle force models to predict muscle forces. At the same time, the musculoskeletal model of subject's weightlifting motor task was built and simulated using the Computed Muscle Control (CMC) method via a motion capture experiment. The results of CMC were compared with the muscle force predictions by the proposed method. The correlation coefficient between two results was 0.99 (p〈0.01). However, the proposed method was easier and more efficiency than the CMC method. It has potential to be used clinically to predict muscle forces in vivo. 展开更多
关键词 WAVELET EMG muscle force WEIGHTLIFTING musculoskeletal motion
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Enhanced domain wall conductivity in photosensitive ferroelectrics Sn_(2)P_(2)S_(6) with full-visible-spectrum absorption 被引量:1
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作者 Jianming Deng Xing’an Jiang +14 位作者 Yanyu Liu Wei Zhao gang tang Yun Li Sheng Xu Jinchen Wang Cheng Zhu Meixia Wu Jing Wang Zishuo Yao Qi Chen Xiaolei Wang Tian-Long Xia Xueyun Wang Jiawang Hong 《Science China Materials》 SCIE EI CAS CSCD 2022年第4期1049-1056,共8页
Recent optical stimulation suggests a vital non-contact pathway to manipulate both macroscopic and microscopic ferroelectric properties and paves the foundation for optoelectronics devices.However,up to date,most opti... Recent optical stimulation suggests a vital non-contact pathway to manipulate both macroscopic and microscopic ferroelectric properties and paves the foundation for optoelectronics devices.However,up to date,most optical-related manipulation of ferroelectric properties is restricted due to their intrinsic bandgap and limited visible light spectrum absorption.Here,we reveal non-oxide Sn_(2)P_(2)S_(6) single crystal possesses full-visible-spectrum absorption(from 300 to 800 nm)with a unique disproportionation mechanism of photoexcited Sn ions and Urbach tail,which is not contradicting to the intrinsic band gap.Interestingly,we observed the existence of conductive domain walls(c-DW)and the light illumination induced significant enhancement of the domain wall conductivity caused by such disproportionation reaction.In addition,the domains separated by c-DW also exhibited noticeable electrical conductivity difference in the presence of optical illumination owing to the interfacial polarization charge with opposite signs.The result provides a novel opportunity for understanding the electrical conductivity behavior of the domains and domain walls in ferroelectrics with full-visible-spectrum absorption and achieving greatly enhanced performances for optoelectronics. 展开更多
关键词 Sn_(2)P_(2)S_(6) FERROELECTRICITY conductive domain walls full-visible-spectrum absorption
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Self-extinguishing and transparent epoxy resin modified by a phosphine oxide-containing bio-based derivative 被引量:1
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作者 gang tang Ruiqing Zhao +5 位作者 Dan Deng Yadong Yang Depeng Chen Bing Zhang Xinliang Liu Xiuyu Liu 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2021年第5期1269-1280,共12页
A phosphine oxide-containing bio-based curing agent was synthesized by addition reaction between furan derivatives and diphenylphosphine oxide.The molecular structure of the as-prepared bio-based curing agent was conf... A phosphine oxide-containing bio-based curing agent was synthesized by addition reaction between furan derivatives and diphenylphosphine oxide.The molecular structure of the as-prepared bio-based curing agent was confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy.Dynamic mechanical analysis results indicated that with the increase of bio-based curing agent content,the glass transition temperature of epoxy/bio-based curing agent composites decreased,which was related to the steric effect of diphenylphosphine oxide species that possibly hinder the curing reaction as well as the reduction in the cross-linking density by mono-functional N-H.By the addition of 7.5 wt-%bio-based curing agent,the resulting epoxy composite achieved UL-94 V-0 rating,in addition to limiting oxygen index of 32.0 vol-%.With the increase of content for the bio-based curing agent,the peak of heat release rate and total heat release of the composites gradually decreased.The bio-based curing agent promoted the carbonization of the epoxy matrix,leading to higher char yield with good thermal resistance.The high-quality char layer served as an effective barrier to retard the diffusion of decomposition volatiles and oxygen between molten polymers and the flame.This study provides a renewable strategy for fabricating flame retardant and transparent epoxy thermoset. 展开更多
关键词 epoxy resin flame retardant furan derivative diphenylphosphine oxide
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