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Wind Speed Prediction Based on Improved VMD-BP-CNN-LSTM Model
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作者 Chaoming Shu bin qin Xin Wang 《Journal of Power and Energy Engineering》 2024年第1期29-43,共15页
Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind s... Amid the randomness and volatility of wind speed, an improved VMD-BP-CNN-LSTM model for short-term wind speed prediction was proposed to assist in power system planning and operation in this paper. Firstly, the wind speed time series data was processed using Variational Mode Decomposition (VMD) to obtain multiple frequency components. Then, each individual frequency component was channeled into a combined prediction framework consisting of BP neural network (BPNN), Convolutional Neural Network (CNN) and Long Short-Term Memory Network (LSTM) after the execution of differential and normalization operations. Thereafter, the predictive outputs for each component underwent integration through a fully-connected neural architecture for data fusion processing, resulting in the final prediction. The VMD decomposition technique was introduced in a generalized CNN-LSTM prediction model;a BPNN model was utilized to predict high-frequency components obtained from VMD, and incorporated a fully connected neural network for data fusion of individual component predictions. Experimental results demonstrated that the proposed improved VMD-BP-CNN-LSTM model outperformed other combined prediction models in terms of prediction accuracy, providing a solid foundation for optimizing the safe operation of wind farms. 展开更多
关键词 Wind Speed Forecast Long Short-Term Memory Network BP Neural Network Variational Mode Decomposition Data Fusion
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分子筛限域单位点钴体系催化芳香族化合物C-H键自调节高效氧化
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作者 党健 李玮杰 +3 位作者 秦斌 柴玉超 武光军 李兰冬 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第2期133-142,共10页
通过芳香族化合物的碳-氢键活化与选择氧化,可以将廉价芳香烃类原料转化为高附加值含氧产品,因此,该反应在基础研究和工业生产中均受到广泛关注.传统的苯乙酮生产工艺存在毒性底物使用、催化剂回收困难、反应条件苛刻以及产物收率低等问... 通过芳香族化合物的碳-氢键活化与选择氧化,可以将廉价芳香烃类原料转化为高附加值含氧产品,因此,该反应在基础研究和工业生产中均受到广泛关注.传统的苯乙酮生产工艺存在毒性底物使用、催化剂回收困难、反应条件苛刻以及产物收率低等问题.通过大量的研究探索,科研人员进一步改进其生产工艺,利用环烷酸钴作为均相催化剂,实现了无溶剂条件下分子氧直接选择氧化乙苯生成苯乙酮.相比均相催化,多相催化在催化剂回收和产物分离方面具有优势,更适合工业化生产.因此,开发用于乙苯选择氧化制苯乙酮的高效稳定多相催化体系非常重要,但具有较大挑战.本文采用原位配体保护的水热合成法将钴配合物(钴-二乙烯三胺)封装在Y型分子筛中,并经进一步焙烧去除配体成功制得Co@Y分子筛催化剂.在无溶剂、无添加剂的条件下,单位点Co作为Co@Y分子筛催化剂的活性位点可催化乙苯选择氧化生成苯乙酮.X射线粉末衍射、透射电镜、紫外可见光吸收光谱和固体核磁共振谱等结果表明,该单位点Co(Co^(2+))通过与骨架氧原子作用稳定限域在Y型分子筛中.为明确Co@Y分子筛催化剂中单位点Co在乙苯氧化反应中所起的重要作用,本文还对比了不同后合成方法所制备的Y分子筛(Co/Y,Co-Y)催化剂及工业环烷酸钴催化剂的催化性能.结果表明,在相同反应条件下,Co@Y分子筛催化剂表现出最高的催化性能,也说明在乙苯氧化反应过程中Co@Y分子筛催化剂的单位点Co有别于上述其他催化剂的活性位点.此外,在Co@Y催化剂热过滤实验中未检测出Co物种浸出,表明Co@Y分子筛催化乙苯氧化反应为多相催化过程,并且在多次循环测试后,Co@Y催化剂结构和反应活性均未发生明显变化.这两项实验均表明Co@Y催化剂具有高稳定性.值得注意的是,在乙苯氧化反应过程中观察到自加速现象,为此进行了对比实验(添加苯甲醛或1-苯乙醇的对比实验)和反应动力学分析.结果表明,痕量苯甲醛或1-苯乙醇的加入会显著改变Co@Y催化剂在乙苯氧化反应中的催化行为,痕量苯甲醛的加入可将反应表观活化能从69.7降至53.7 kJ/mol.本文也通过第一性原理密度泛函理论(DFT)计算系统研究了Co@Y分子筛催化剂单位点Co处乙苯选择氧化反应机理及反应过程中自加速现象产生的原因.DFT计算结果结合上述对比实验和反应动力学分析结果表明,加入痕量苯甲醛或者1-苯乙醇后部分乙苯会直接氧化生成苯乙酮,而非通过乙苯→1-苯乙醇→苯乙酮的途径生成苯乙酮.DFT计算结果也阐明反应过程中自加速现象的产生源于单位点Co处活性氧物种(O^(*))的生成.该活性氧物种在乙苯、苯甲醛和1-苯乙醇的氧化途径中均能自发生成,并且该物种类似“引发剂”促使后续更多链式反应的发生,在乙苯氧化反应过程中具有非常重要的作用.综上所述,本文为理解芳香族化合物碳-氢键选择氧化实验现象与催化作用机制提供了有益见解,可为理性设计开发更高效的催化剂提供新思路. 展开更多
关键词 碳-氢键活化 多相催化 Co@Y分子筛催化剂 自加速 活性氧物种
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The underlying mechanism of variety–water–nitrogen–stubble damage interactions on yield formation in ratoon rice with low stubble height under mechanized harvesting 被引量:2
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作者 Jingnan Zou Ziqin Pang +11 位作者 Zhou Li Chunlin Guo Hongmei Lin Zheng Li Hongfei Chen Jinwen Huang Ting Chen Hailong Xu bin qin Puleng Letuma Weiwei Lin Wenxiong Lin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期806-823,共18页
Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary ... Agronomic measures are the key to promote the sustainable development of ratoon rice by reducing the damage from mechanical crushing to the residual stubble of the main crop, thereby mitigating the impact on axillary bud sprouting and yield formation in ratoon rice. This study used widely recommended conventional rice Jiafuzhan and hybrid rice Yongyou 2640 as the test materials to conduct a four-factor block design field experiment in a greenhouse of the experimental farm of Fujian Agricultural and Forestry University, China from 2018 to 2019.The treatments included fertilization and no fertilization, alternate wetting and drying irrigation and continuous water flooding irrigation, and plots with and without artificial crushing damage on the rice stubble. At the same time, a 13C stable isotope in-situ detection technology was used to fertilize the pot experiment. The results showed significant interactions among varieties, water management, nitrogen application and stubble status.Relative to the long-term water flooding treatment, the treatment with sequential application of nitrogen fertilizer coupled with moderate field drought for root-vigor and tiller promotion before and after harvesting of the main crop, significantly improved the effective tillers from low position nodes. This in turn increased the effective panicles per plant and grains per panicle by reducing the influence of artificial crushing damage on rice stubble and achieving a high yield of the regenerated rice. Furthermore, the partitioning of 13C assimilates to the residual stubble and its axillary buds were significantly improved at the mature stage of the main crop, while the translocation rate to roots and rhizosphere soil was reduced at the later growth stage of ratooning season rice. This was triggered by the metabolism of hormones and polyamines at the stem base regulated by the interaction of water and fertilizer at this time. We therefore suggest that to achieve a high yield of ratoon rice with low stubble height under mechanized harvesting, the timely application of nitrogen fertilizer is fundamental,coupled with moderate field drying for root-vigor preservation and tiller promotion before and after the mechanical harvesting of the main crop. 展开更多
关键词 mechanized harvesting ratoon rice rice stubble yield attributes
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Characteristics of early gastric tumors with different differentiation and predictors of long-term outcomes after endoscopic submucosal dissection
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作者 Hong-Yi Zhu Jie Wu +7 位作者 Yuan-Miao Zhang Fang-Lan Li Jin Yang bin qin Jiong Jiang Ning Zhu Meng-Yao Chen Bai-Cang Zou 《World Journal of Gastroenterology》 SCIE CAS 2024年第14期1990-2005,共16页
BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological char... BACKGROUND Gastric cancer is a common malignant tumor of the digestive tract,and endosco-pic submucosal dissection(ESD)is the preferred treatment for early-stage gastric cancer.The analysis of the epidemiological characteristics of gastric mucosal tumors with different differentiation degrees and the influencing factors of long-term ESD efficacy may have certain significance for revealing the development of gastric cancer and ESD.AIM To analyze the features of gastric mucosal tumors at different differentiation levels,and to explore the prognostic factors of ESD.METHODS We retrospectively studied 301 lesions in 285 patients at The Second Affiliated Hospital of Xi'an Jiaotong University from 2014 to 2021,according to the latest Japanese guidelines(sixth edition),and divided them into low-grade intrae-pithelial neoplasia(LGIN),high-grade intraepithelial neoplasia(HGIN),and computed tomography at 3,6 and 12 months after ESD.We compared clinicopathologic characteristics,ESD efficacy,and complications with different degrees of differentiation,and analyzed the related factors associated with ESD.RESULTS HGIN and differentiated carcinoma patients were significantly older compared with LGIN patients(P<0.001)and accounted for more 0-IIc(P<0.001),atrophic gastritis was common(P<0.001),and irregular microvascular patterns(IMVPs)and demarcation lines(DLs)were more obvious(P<0.001).There was more infiltration in the undifferentiated carcinoma tissue(P<0.001),more abnormal folds and poorer mucosal peristalsis(P<0.001),and more obvious IMVPs,irregular microsurface patterns and DLs(P<0.05)than in the LGIN and HGIN tissues.The disease-free survival rates at 2,5,and 8 years after ESD were 95.0%,90.1%,and 86.9%,respectively.Undifferen-tiated lesions(HR 5.066),white moss(HR 7.187),incomplete resection(HR 3.658),and multiple primary cancers(HR 2.462)were significantly associated with poor prognosis.CONCLUSION Differentiations of gastric mucosal tumors have different epidemiological and endoscopic characteristics,which are closely related to the safety and efficacy of ESD. 展开更多
关键词 Gastric mucosal epithelial neoplasia Differentiated early gastric cancer Undifferentiated early gastric cancer Endoscopic submucosal dissection Long-term outcomes
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Heterostructured Mn_(3)O_(4)-MnS Multi-Shelled Hollow Spheres for Enhanced Polysulfide Regulation in Lithium-Sulfur Batteries 被引量:2
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作者 bin qin Qun Wang +8 位作者 Weiqi Yao Yifei Cai Yuhan Chen Pengcheng Wang Yongchun Zou Xiaohang Zheng Jian Cao Junlei Qi Wei Cai 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期436-444,共9页
Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and... Constructing heterojunctions and hollow multi-shelled structures can render materials with fascinating physicochemical properties,and have been regarded as two promising strategies to overcome the severe shuttling and sluggish kinetics of polysulfide in lithium-sulfur(Li-S)batteries.However,a single strategy can only take limited effect.Modulating catalytic hosts with synergistic effects are urgently desired.Herein,Mn_(3)O_(4)-MnS heterogeneous multi-shelled hollow spheres are meticulously designed by controlled sulfuration of Mn2O3 hollow spheres,and then applied as advanced encapsulation hosts for Li-S batteries.Benefiting from the separated spatial confinement by hollow multi-shelled structure,ample exposed active sites and built-in electric field by heterogeneous interface,and synergistic effects between Mn_(3)O_(4)(strong adsorption)and MnS(fast conversion)components,the assembled battery achieves prominent rate capability and decent cyclability(0.016%decay per cycle at 2 C,1000 cycles).More crucially,satisfactory areal capacity reaches up to 7.1 mAh cm^(-2)even with high sulfur loading(8.0 mg cm^(-2))and lean electrolyte(E/S=4.0 pL mg^(-1))conditions.This work will provide inspiration for the rational design of hollow multi-shelled heterostructure for various electrocatalysis applications. 展开更多
关键词 ELECTROCATALYST heterojunction host hollow multi-shelled structure Li-S battery Mn_(3)O_(4)-MnS
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Dynamic compressive response of porcine muscle measured using a split Hopkinson bar system with a pair of PVDF force transducers 被引量:1
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作者 Yao-ke Wen Liang Xu +2 位作者 Ai-jun Chen Fang-dong Dong bin qin 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2023年第10期298-305,共8页
The classic metallic Split Hopkinson Pressure Bar(SHPB)cannot capture the transmitted signal accurately when measuring soft biological tissue,because of the very low wave impedance and strength of this material.So the... The classic metallic Split Hopkinson Pressure Bar(SHPB)cannot capture the transmitted signal accurately when measuring soft biological tissue,because of the very low wave impedance and strength of this material.So the dynamic compressive response of porcine muscle has been investigated by using a modified SHPB.The forces on both ends of the sample measured using Polyvinylidene fluor(PVDF)transducers were applied to calculate the stress in the specimen instead of the strain gauge signal on the transmitted bar.Moreover,a circular cardboard disk pulse shaper was applied for generating a suitable incident pulse to achieve stress equilibrium and constant strain rates in the specimens.Then,the dynamic mechanical properties of porcine muscle parallel and perpendicular to the fiber directions were measured,and the stress equilibrium process during loading was analyzed,as well as the inertia-induced extra stress being corrected.Furthermore,quasi-static tests were conducted at two different strain rates to investigate the strain rate dependence using a universal material testing machine.The results show that the stress-strain curves are sensitive to strain rate in the two different loading directions.The compressive stress perpendicular to the fiber direction is stiffer than that parallel to the fiber direction.In addition,a strain rate-dependent constitutive model was developed based on the mechanical response of the muscle at different strain rates and fitted to the experimental data.The results show that the overall fit is good,and the constitutive model could describe the muscle's dynamic mechanical properties. 展开更多
关键词 PVDF Hopkinson bar Porcine muscle Dynamic mechanical properties Constitutive model
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Spiro-based triphenylamine molecule with steric structure as a cathode material for high-stable all organic lithium dual-ion batteries
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作者 Liya Huang Zehao Yu +4 位作者 Liubin Wang bin qin Fengshi Cai Zhihao Yuan Zhiqiang Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期24-31,I0003,共9页
Redox p-type organic compounds are promising cathode materials for dual-ion batteries.However,the triphenylamine-based polymers usually with agglomerate and intertwined molecular chain nature limit the maximum reactio... Redox p-type organic compounds are promising cathode materials for dual-ion batteries.However,the triphenylamine-based polymers usually with agglomerate and intertwined molecular chain nature limit the maximum reaction of their active sites with large-sized anions.Herein,we demonstrate the application of a small molecule with rigid spirofluorene structu re,namely 2,2’,7,7’-tetrakis(diphenylamine)-9,9’-spirobifluorene(Spiro-TAD),as a cathode material for lithium dual-ion batteries.The inherent sterical structure endows the Spiro-TAD with good chemical stability and large internal space for fast diffusion kinetics of anions in the organic electrolyte.As a result,the Spiro-TAD electrode shows significant insolubility and less steric hindrance,and gives a high actual capacity of 109 mA h g^(-1)(active groups utilization ratio approximately 100%) at 50 mA g^(-1)with a high discharge voltage of 3.6 V(vs.Li+/Li),excellent rate capability(60 mA h g^(-1)at 2000 mA g^(-1)) and extremely stable cycling life(98.4% capacity retention after 1400 cycles at 500 mA g^(-1)) in half cells.Such good electrochemical performance is attributed to the robust and rapid adsorption/desorption of ClO4-anions,which can be proved by the in-situ FTIR and XPS.Moreover,an all-organic lithium dual-ion battery(a-OLDIBs) is constructed using the Spiro-TAD as cathode and 3,4,9,10-Perylenetetracarboxylic diimide(PTCDI) as anode and displays long-term cycling performance of 87.5 mA h g^(-1)after 800 cycles.This study will stimulate further developments in designing all organic battery systems. 展开更多
关键词 Spiro-basedmolecule Cathodematerial P-typeorganiccompounds Longcycling life All organic lithiumdual-ionbatteries
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基于案例推理的高校“双创”实现路径优选 被引量:1
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作者 宾芹 向琳 《创新与创业教育》 2020年第1期81-85,共5页
"双创"是现代化经济体系建设的战略支撑之一,高校是创新创业发展的重要基地。但目前高校的"双创"建设没有全面系统的方案作为参考,其发展参差不齐。通过调查高校"双创"建设的成功案例,进行比较分析,发现... "双创"是现代化经济体系建设的战略支撑之一,高校是创新创业发展的重要基地。但目前高校的"双创"建设没有全面系统的方案作为参考,其发展参差不齐。通过调查高校"双创"建设的成功案例,进行比较分析,发现创新创业平台、创新创业教育、创新团队、导师制、校企合作五个方面对高校"双创"影响较为显著,并针对性地提出了对策建议,以期为高校"双创"和创新型国家建设提供有益借鉴。 展开更多
关键词 “双创” 导师制 校企合作
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内镜热损伤术后息肉样结节瘢痕的病理性质及处理策略探讨 被引量:1
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作者 杨津 秦斌 +8 位作者 朱洪怡 伍洁 秦赟 姜炅 程妍 张莉 全晓静 龚均 邹百仓 《中国内镜杂志》 2022年第4期81-85,共5页
目的 总结内镜热损伤治疗术后息肉样结节瘢痕(PNS)的病理性质和发生机制,并探讨处理策略。方法 选择2015年3月-2019年3月于该科行内镜氩等离子体凝固术(APC)、内镜下黏膜切除术(EMR)和内镜黏膜下剥离术(ESD)治疗胃黏膜增生性病变的患者... 目的 总结内镜热损伤治疗术后息肉样结节瘢痕(PNS)的病理性质和发生机制,并探讨处理策略。方法 选择2015年3月-2019年3月于该科行内镜氩等离子体凝固术(APC)、内镜下黏膜切除术(EMR)和内镜黏膜下剥离术(ESD)治疗胃黏膜增生性病变的患者,回顾性分析发生PNS的7例患者的诊治及随访资料。同时,在中国知网(CNKI)、万方数据知识服务平台、中国生物医学数据库等中国数据库以及PubMed、Science Direct Online (SDOL)等国外数据库中检索相关文献,总结PNS的病理特征及随访结果。结果 临床资料:该科内镜治疗黏膜增生性病变后PNS发生率为1.21%(7/579),男5例,女2例,病变均位于胃窦。4例追加了ESD,术后标本切缘病理阴性,但随访复查中,手术瘢痕处再次发现息肉样结节。另外3例PNS未追加治疗,其中1例术后3个月发现息肉样结节,未作处理,术后6个月复查结节消失。文献检索结果:中文数据库无相关文献,在Science Direct Online (SDOL)和PubMed中检索到2篇相关文献,1篇为ESD术后发生PNS的个案报道,另一篇为多中心研究,前一篇文献资料包含在后一篇文献中。多中心研究文献显示:ESD术后PNS总体发病率为1.23%,各中心PNS发病率为0.15%~11.40%,所有发生PNS的患者原发病变均位于胃远端,长期随访无恶性肿瘤复发,17.86%的病例PNS于平均随访18个月后消失。结论 只要原发病变根治性切除,PNS在组织学上仅显示为再生和增生性组织,应被视为良性病变,除定期复查外,不需任何干预,即使内镜下切除,仍有可能复发。 展开更多
关键词 息肉样结节瘢痕 热损伤治疗术 病理 发生机制 处理策略
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Parameter selection of support vector regression based on hybrid optimization algorithm and its application 被引量:9
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作者 Xin WANG Chunhua YANG +1 位作者 bin qin Weihua GUI 《控制理论与应用(英文版)》 EI 2005年第4期371-376,共6页
Choosing optimal parameters for support vector regression (SVR) is an important step in SVR. design, which strongly affects the pefformance of SVR. In this paper, based on the analysis of influence of SVR parameters... Choosing optimal parameters for support vector regression (SVR) is an important step in SVR. design, which strongly affects the pefformance of SVR. In this paper, based on the analysis of influence of SVR parameters on generalization error, a new approach with two steps is proposed for selecting SVR parameters, First the kernel function and SVM parameters are optimized roughly through genetic algorithm, then the kernel parameter is finely adjusted by local linear search, This approach has been successfully applied to the prediction model of the sulfur content in hot metal. The experiment results show that the proposed approach can yield better generalization performance of SVR than other methods, 展开更多
关键词 Support vector regression Parameters tuning Hybrid optimization Genetic algorithm(GA)
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Experimental study of transient pressure wave in the behind armor blunt trauma induced by different rifle bullets 被引量:5
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作者 Rui-guo Han Yong-jie Qu +3 位作者 Wen-min Yan bin qin Shu Wang Jian-zhong Wang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2020年第4期900-909,共10页
Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave i... Pressure wave plays an important role in the occurrence of behind armor blunt trauma(BABT),and ballistic gelatin is widely used as a surrogate of biological tissue in the research of BABT.Comparison of pressure wave in the gelatin behind armor for different rifle bullets is lacking.The aim of this study was to observe dynamic changes in pressure wave induced by ballistic blunt impact on the armored gelatin block and to compare the effects of bullet type on the parameters of the transient pressure wave.The gelatin blocks protected with National Institute of Justice(NIJ) class III bulletproof armor were shot by three types of rifle bullet with the same level of impact energy.The transient pressure signals at five locations were recorded with pressure sensors and three parameters(maximum pressure,maximum pressure impulse,and the duration of the first positive phase) were determined and discussed.The results indicated that the waveform and the twin peak of transient pressure wave were not related to the bullet type.However,the values of pressure wave's parameters were significantly affected by bullet type.Additionally,the attenuation of pressure amplitude followed the similar law for the three ammunitions.These findings may be helpful to get some insight in the BABT and improve the structure design of bullet. 展开更多
关键词 Behind armor blunt trauma Ballistic gelatin Pressure wave Body armor
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Decreased expression of gastrokine 1 in gastric mucosa of gastric cancer patients 被引量:1
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作者 Xiao-Yan Guo Lei Dong +2 位作者 bin qin Jiong Jiang A-Meng Shi 《World Journal of Gastroenterology》 SCIE CAS 2014年第44期16702-16706,共5页
AIM: To investigate the expression of gastrokine 1 (GKN1) in normal gastric mucosa, precancerous lesions and gastric cancer tissues, and to analyse its correlations with tumour site and pathological pattern.
关键词 Gastrokine 1 Gastric cancer Gastric mucosa EXPRESSION
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Amphotericin B release rate is the link between drug status in the liposomal bilayer and toxicity
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作者 Yuri Svirkin Jaeweon Lee +11 位作者 Richard Marx Seongkyu Yoon Nelson Landrau Md Abul Kaisar bin qin Jin H.Park Khondoker Alam Darby Kozak Yan Wang Xiaoming Xu Jiwen Zheng Benjamin Rivnay 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2022年第4期544-556,共13页
Amphotericin B(AmB)is an amphiphilic drug commonly formulated in liposomes and administered intravenously to treat systemic fungal infections.Recent studies on the liposomal drug product have shed light on the AmB agg... Amphotericin B(AmB)is an amphiphilic drug commonly formulated in liposomes and administered intravenously to treat systemic fungal infections.Recent studies on the liposomal drug product have shed light on the AmB aggregation status in the bilayer,which heat treatment(curing)modifies.Although toxicity was found related to aggregation status-loose aggregates significantly more toxic than tight aggregates-the precise mechanism linking aggregation and toxicitywas notwell understood.This study directlymeasured drug release rate fromvarious AmB liposomal preparations made with modified curing protocols to evaluate correlations among drug aggregation state,drug release,and in vitro toxicity.UV–Vis spectroscopy of these products detected unique curing-induced changes in the UV spectral features:a∼25nm blue-shift of the main absorption peak(λ_(max))in aqueous buffer and a decrease in the OD_(346)/OD_(322) ratio upon thermal curing,reflecting tighter aggregation.In vitro release testing(IVRT)data showed,by applying and fitting first-order release kinetic models for one or two pools,that curing impacts two significant changes:a 3–5-fold drop in the overall drug release rate and a ten-fold decrease in the ratio between the loosely aggregated and the tightly aggregated,more thermodynamically stable drug pool.The kinetic data thus corroborated the trend independently deduced from the UV–Vis spectral data.The in vitro toxicity assay indicated a decreased toxicity with curing,as shown by the significantly increased concentration,causing half-maximal potassium release(TC50).The data suggest that the release of AmB requires dissociation of the tight complexes within the bilayer and that the reduced toxicity relates to this slower rate of dissociation.This study demonstrates the relationship between AmB aggregation status within the lipid bilayer and drug release(directly measured rate constants),providing a mechanistic link between aggregation status and in vitro toxicity in the liposomal formulations. 展开更多
关键词 Amphotericin B UV–Vis Spectrum Drug Release In Vitro Toxicity Aggregation Status Liposomes
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Design and development of the beamline for a proton therapy system
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作者 bin qin Xu Liu +8 位作者 Qu-Shan Chen Dong Li Wen-Jie Han Ping Tan Zhong-Qi Zhang Chong Zhou Ao-Te Chen Yi-Cheng Liao Wei Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第12期53-63,共11页
A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the ... A proton therapy(PT)facility with multiple treatment rooms based on the superconducting cyclotron scheme is under development at Huazhong University of Science and Technology(HUST).This paper attempts to describe the design considerations and implementation of the PT beamline from a systematic viewpoint.Design considerations covering beam optics and the influence of high-order aberrations,beam energy/intensity modulation,and beam orbit correction are described.In addition to the technical implementation of the main beamline components and subsystems,including the energy degrader,fast kicker,beamline magnets,beam diagnostic system,and beamline control system are introduced. 展开更多
关键词 Proton therapy BEAMLINE Beam optics Beam energy/intensity modulation
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Bilobalide inhibits the expression of aquaporin 1, 4 and glial fibrillary acidic protein in rat brain tissue after permanent focal cerebral ischemia
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作者 Haiming qin Fulin Song +4 位作者 Hongguang Han Hong Ou Xingwen Zhai bin qin Song You 《Neural Regeneration Research》 SCIE CAS CSCD 2011年第27期2105-2111,共7页
The present results demonstrated that in an adult rat model of permanent middle cerebral artery occlusion (pMCAO), pretreatment with bilobalide reduced brain water content and infarct area, down-regulated aquaporin ... The present results demonstrated that in an adult rat model of permanent middle cerebral artery occlusion (pMCAO), pretreatment with bilobalide reduced brain water content and infarct area, down-regulated aquaporin 1, 4 mRNA expression in brain edema tissue, then inhibited their synthesis in the striatum, in particular at the early stage of ischemia (at 8 hours after pMCAO), inhibited glial fibrillary acidic protein expression, and lightened reactive gliosis. These data sug-gest that bilobalide attenuates brain edema formation due to reduced expression of aquaporins. 展开更多
关键词 bilobalide aquaporin brain edema permanent middle cerebral artery occlusion glial fibrillary acidic protein neural regeneration
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Zeolite-encaged gold catalysts for the oxidative condensation of furfural
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作者 Weijie Li Mingyang Gao +2 位作者 bin qin Xin Deng Landong Li 《Frontiers of Chemical Science and Engineering》 SCIE EI CSCD 2024年第8期67-77,共11页
The oxidative condensation between renewable furfural and fatty alcohols is a crucial avenue for producing high-quality liquid fuels and valuable furan derivatives.The selectivity control in this reaction process rema... The oxidative condensation between renewable furfural and fatty alcohols is a crucial avenue for producing high-quality liquid fuels and valuable furan derivatives.The selectivity control in this reaction process remains a significant challenge.Herein,we report the strategy of confining well dispersed gold species within ZSM-5 structure to construct highly active Au@ZSM-5 zeolite catalysts for the oxidative condensation of furfural.Characterization results and spectroscopy analyses demonstrate the efficient encapsulation of isolated and cationic Au clusters in zeolite structure.Au@ZSM-5(K)catalyst shows remarkable performance with 69.7%furfural conversion and 90.2%furan-2-acrolein selectivity as well as good recycle stability.It is revealed that the microstructure of ZSM-5 zeolite can significantly promote oxidative condensation activity through confinement effects.This work presents an explicit example of constructing zeolite encaged noble metal catalysts toward targeted chemical transformations. 展开更多
关键词 ZEOLITE ENCAPSULATION GOLD oxidative condensation FURFURAL
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误诊为精神分裂症的额颞叶痴呆1例
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作者 许吉怡 梁慧 +1 位作者 秦斌 赵程 《中华全科医师杂志》 2023年第4期420-422,共3页
额颞叶痴呆是早发型痴呆的主要病因之一,临床误诊率较高,因此本文报道1例早期误诊为精神分裂症的额颞叶痴呆,旨在帮助临床医生了解其发病特点,鉴别精神分裂症与额颞叶痴呆,采用合理治疗延缓患者疾病进展。
关键词 额颞叶痴呆 精神分裂症 鉴别诊断
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基于转化-合金化机制的钠离子电池PbSe@CNTs负极材料
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作者 赵东东 张宁 +4 位作者 赵小莹 刘宁博 覃彬 仇满德 王刘彬 《Science China Materials》 SCIE EI CAS CSCD 2023年第1期61-68,共8页
钠离子电池作为新型的储能电池体系因钠资源储量丰富、成本低廉等优势有望填补锂离子电池在某些应用领域的空缺,非常适用于大规模储能领域.然而,高容量储钠负极材料仍然需要进一步研究.本文以废旧铅酸电池的回收铅和商业化硒粉为原料,... 钠离子电池作为新型的储能电池体系因钠资源储量丰富、成本低廉等优势有望填补锂离子电池在某些应用领域的空缺,非常适用于大规模储能领域.然而,高容量储钠负极材料仍然需要进一步研究.本文以废旧铅酸电池的回收铅和商业化硒粉为原料,采用机械球磨法制备了纳米硒化铅与碳纳米管(PbSe@CNTs)的复合材料.碳纳米管网络缠绕在PbSe纳米粒子上,可有效抑制纳米粒子的团聚,同时提高了电子导电性.纳米级的PbSe和拓扑结构的CNTs有利于电解液的渗透,缩短了Na+和电子的传输路径,缓解了脱嵌钠过程中的机械应变,提高了倍率和长循环稳定性能.PbSe@CNTs电极在20 mA g^(-1)电流密度下具有597 mA h g^(-1)的可逆比容量,在100 m A g^(-1)循环100圈仍保持458.9 mA h g^(-1)的可逆比容量,容量保持率为88%.通过X射线衍射和拉曼光谱分析,证实了PbSe的储钠机理为两步转化-合金化过程,反应方程式为PbSe+5.75Na++5.75e-?0.25Na15Pb4+Na2Se. 展开更多
关键词 钠离子电池 负极材料 电子导电性 锂离子电池 储能电池 反应方程式 碳纳米管 机械球磨法
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Efficient Heterogeneous Hydroformylation over Zeolite-Encaged Isolated Rhodium Ions
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作者 Weixiang Shang bin qin +6 位作者 Mingyang Gao Xuetao qin Yuchao Chai Guangjun Wu Naijia Guan Ding Ma Landong Li 《CCS Chemistry》 CSCD 2023年第7期1526-1539,共14页
Alkene hydroformylation is an extremely important industry process currently accomplished via homogeneous catalysis.Heterogeneous hydroformylation is being avidly pursued as a more economical and sustainable process.H... Alkene hydroformylation is an extremely important industry process currently accomplished via homogeneous catalysis.Heterogeneous hydroformylation is being avidly pursued as a more economical and sustainable process.Herein,we report the construction of zeolite-encaged rhodium catalyst for efficient hydroformylation.Through a facile in situ hydrothermal strategy,isolated Rh^(δ+)(δ=2.5)can be encaged in faujasite and efficiently stabilized via interaction with framework oxygen atoms,producing a Rh@Y model catalyst with well-defined rhodium sites and coordination environment.Rh@Y exhibits high catalytic activity,perfect chemoselectivity,and recyclability in 1-hexene hydroformylation under mild reaction conditions,making it a robust heterogeneous catalyst for potential applications.A state-of-the-art turnover frequency value of 6567 molC=C/molRh/h for Rh@Y can be achieved in 1-hexene hydroformylation at 393 K,outperforming all heterogeneous catalysts and most homogeneous catalysts under comparable conditions.With the well-defined structure of Rh@Y,the detailed mechanism of alkene hydroformylation can be interpreted via theoretical calculations,and the advantages of heterogeneous hydroformylation are well explained.This work provides a promising solution toward efficient heterogeneous noble metal catalysis by encaging stable isolated ions in a zeolite matrix. 展开更多
关键词 ZEOLITE isolated rhodium site heterogeneous catalysis HYDROFORMYLATION mechanism
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Design of a large momentum acceptance proton therapy gantry utilizing AG-CCT magnets
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作者 Yi-Cheng Liao Xu Liu +3 位作者 Wei Wang Zi-Yi Yang Qu-Shan Chen bin qin 《Nuclear Science and Techniques》 SCIE EI CAS 2024年第10期59-69,共11页
The application of superconducting(SC)technology enables magnets to excite strong fields with small footprints,which has great potential for miniaturizing proton therapy gantries.However,the slow ramping rate of SC ma... The application of superconducting(SC)technology enables magnets to excite strong fields with small footprints,which has great potential for miniaturizing proton therapy gantries.However,the slow ramping rate of SC magnets results in a low treatment efficiency compared with normal-conducting(NC)gantries.To address this problem,this study proposes a compact proton therapy gantry design with a large momentum acceptance utilizing alternating-gradient canted-cosine-theta(AG-CCT)SC magnets.In our design,a high-transmission degrader is mounted in the middle of the gantry,and the upstream beamline employs NC magnets with small apertures.Downstream of the degrader,large-bore AG-CCT magnets with strong alternating focusing gradients are set symmetrically as a local achromat,which realizes a momentum acceptance of 20%(or 40%in the energy domain).Therefore,only three magnetic working points are required to cover a treatment energy of 70-230 Me V.Owing to the large momentum acceptance,the proton beam after the degrader can be directly delivered to the isocenter without truncating its energy spectrum,which can significantly increase the treatment efficiency but causes severe dispersion effects during pencil beam scanning.Therefore,a compensation method was introduced by tuning the normal and skewed quadrupoles during the scanning process.As a result,the new gantry not only presents a remarkable reduction in the size and weight of the facility but also shows good potential for fast treatment. 展开更多
关键词 Alternating-gradient canted-cosine-theta magnets Large momentum acceptance gantry Pencil beam scanning Proton therapy
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