期刊文献+
共找到74篇文章
< 1 2 4 >
每页显示 20 50 100
Unraveling the reaction mechanism of high reversible capacity CuP_(2)/C anode with native oxidation PO_(x) component for sodium-ion batteries
1
作者 Huixin Chen Chen Zhao +4 位作者 Hongjun Yue Guiming Zhong xiang han Liang Yin Ding Chen 《Chinese Chemical Letters》 2025年第1期574-578,共5页
Phosphorus-based anode is a promising anode for sodium-ion batteries(SIBs)due to its high specific capacity,however,suffers from poor electronic conductivity and unfavorable electrochemical reversibility.Incorporating... Phosphorus-based anode is a promising anode for sodium-ion batteries(SIBs)due to its high specific capacity,however,suffers from poor electronic conductivity and unfavorable electrochemical reversibility.Incorporating metals such as copper(Cu)into phosphorus has been demonstrated to not only improve the electronic conductivity but also accommodate the volume change during cycling,yet the underline sodiation mechanism is not clear.Herein,take a copper phosphide and reduced graphene oxide(CuP_(2)/C)composite as an example,which delivers a high reversible capacity of>900 mAh/g.Interestingly,it is revealed that the native oxidation PO_(x)components of the CuP_(2)/C composite show higher electrochemical reversibility than the bulk Cu P_(2),based on a quantitative analysis of high-resolution solid-state^(31)P NMR,ex-situ XPS and synchrotron X-ray diffraction characterization techniques.The sodiation products Na_(3)PO_(4) and Na_(4)P_(2)O_(7) derived from PO_(x) could react with Na-P alloys and regenerate to PO_(x) during charge process,which probably accounts for the high reversible capacity of the Cu P_(2)/C anode.The findings also illustrate that the phosphorus transforms into nanocrystalline Na_(3)P and Na_(x)P alloys,which laterally shows crystallization-amorphization evolution process during cycling. 展开更多
关键词 CuP_(2)/C composite POx component Reaction mechanism Solid-state NMR Sodium-ion batteries
原文传递
Monothetic and conductive network and mechanical stress releasing layer on micron-silicon anode enabling high-energy solid-state battery 被引量:1
2
作者 xiang han Min Xu +7 位作者 Lan-Hui Gu Chao-Fei Lan Min-Feng Chen Jun-Jie Lu Bi-Fu Sheng Peng Wang Song-Yan Chen Ji-Zhang Chen 《Rare Metals》 SCIE EI CAS CSCD 2024年第3期1017-1029,共13页
Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state electrolyt... Silicon has ultrahigh capacity,dendrite-free alloy lithiation mechanism and low cost and has been regarded as a promising anode candidate for solid-state battery.Owing to the low infiltration of solid-state electrolyte(SSE),not the unstable solid-electrolyte interphase(SEI),but the huge stress during lithiation-and delithiation-induced particle fracture and conductivity lost tend to be the main issues.In this study,starting with micron-Si,a novel monothetic carbon conductive framework and a MgO coating layer are designed,which serve as electron pathway across the whole electrode and stress releasing layer,respectively.In addition,the in situ reaction between Si and SSE helps to form a LiF-rich and mechanically stable SEI layer.As a result,the mechanical stability and charge transfer kinetics of the uniquely designed Si anode are significantly improved.Consequently,high initial Coulombic efficiency,high capacity and durable cycling stability can be achieved by applying the Si@MgO@C anode in SSB.For example,high specific capacity of 3224.6 mAh·g^(-1)and long cycling durability of 200 cycles are achieved.This work provides a new concept for designing alloy-type anode that combines surface coating on particle and electrode structure design. 展开更多
关键词 Lithium-ion battery(LIB) Solid-state electrolyte(SSE) Silicon anode Stress relief Coating
原文传递
栀子多糖的提取纯化及其体外抗氧化活性研究 被引量:1
3
作者 林平冬 向韩 +2 位作者 岳稳 刘景 陈鑫珠 《农业工程学报》 北大核心 2025年第3期309-317,共9页
为优化栀子多糖的提取工艺,对栀子多糖粗提物进行纯化并研究其体外抗氧化活性。采用单因素及正交试验优化超声波辅助法提取栀子多糖的工艺,利用阴离子交换树脂纯化栀子粗多糖。通过测定栀子多糖的还原力和自由基清除能力,以及栀子多糖... 为优化栀子多糖的提取工艺,对栀子多糖粗提物进行纯化并研究其体外抗氧化活性。采用单因素及正交试验优化超声波辅助法提取栀子多糖的工艺,利用阴离子交换树脂纯化栀子粗多糖。通过测定栀子多糖的还原力和自由基清除能力,以及栀子多糖对热应激鸡肝细胞中氧化损伤相关标志物水平的影响,评价栀子多糖的抗氧化作用。结果表明:1)栀子多糖最佳提取工艺参数为:料液比1∶20,提取时间50 min、提取温度80℃,提取次数1次,此条件下栀子粗多糖得率为11.5%。经初步纯化后的栀子多糖(命名为GP)的多糖含量为45.3%(以葡萄糖计)。2)5 mg/mL的GP最大还原力接近同等浓度下维生素C的一半;对·OH、DPPH·和ABTS+·的清除率分别为63.5%、96.6%、99.3%,半数有效浓度(EC_(50))分别为3.8、0.1、1.1 mg/mL。3)0.1~0.4 mg/mL的GP对鸡肝细胞存活率无显著影响(P>0.05);与热应激组相比,GP组细胞的活性氧(reactive oxygen species,ROS)、谷草转氨酶(aspartate aminotransferase,AST)、丙二醛(malondialdehyde,MDA)含量均显著降低(P<0.05),超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)活性及总抗氧化能力(total antioxidant capacity,TAOC)水平均显著升高(P<0.05),并与阳性对照组和空白对照组相当或优于空白对照组。综上,该研究优选了栀子多糖的提取工艺,并验证了该工艺条件下提取得到的栀子多糖具有良好的体外抗氧化活性,为栀子多糖作为多糖类抗氧化剂深入开发利用提供理论依据。 展开更多
关键词 提取 纯化 栀子多糖 抗氧化活性 鸡肝细胞 热应激 氧化损伤
在线阅读 下载PDF
泥石流易发性间谍技术随机森林模型研究——以岷江上游为例 被引量:2
4
作者 陈宇涛 李宁 +5 位作者 常鸣 幸夫诚 向晗 李晋生 杨瑞 陈子龙 《中国地质灾害与防治学报》 2025年第4期137-149,共13页
泥石流作为一种由强降雨或冰雪融化引发的高浓度非均质流体,具有复杂的形成和运动过程。评估泥石流的易发性对于灾害监测与应对具有重要的实际意义。传统方法难以准确预测泥石流的发生,因此近年来机器学习算法在该领域的应用逐渐增多。... 泥石流作为一种由强降雨或冰雪融化引发的高浓度非均质流体,具有复杂的形成和运动过程。评估泥石流的易发性对于灾害监测与应对具有重要的实际意义。传统方法难以准确预测泥石流的发生,因此近年来机器学习算法在该领域的应用逐渐增多。文章以岷江上游为例,提出一种基于间谍技术(SPY)的随机森林模型SPY-RF,用于构建泥石流易发性评价系统。SPY方法通过对未标记数据进行伪负样本生成,克服了不平衡数据集在负样本获取上的局限性,提高了模型的区分能力。在研究中选取14个评价因子,如沟壑密度、岩性、流域面积等,结合遥感影像和地质灾害数据构建泥石流数据集。通过SPY技术优化负样本的获取,结合随机森林模型对泥石流易发性进行建模。结果显示:SPY-RF模型和RF模型的AUC值分别为0.98,0.93,且SPY-RF模型性能指标整体优于RF模型,SPY-RF模型在预测泥石流易发性方面表现出较高的精确度和稳定性,极高易发区与现有泥石流点的分布吻合,在极低和低风险区域也能识别泥石流点。在负样本获取和筛选策略上,采用SPY技术显著提高了负样本的质量,从而提升了模型的预测精度和可靠性。为岷江上游地区泥石流风险管理提供了参考依据。 展开更多
关键词 泥石流 易发性 随机森林 间谍技术 岷江上游流域
在线阅读 下载PDF
2022年马尔康6.0级震群同震滑坡空间分布规律分析
5
作者 向晗 李宁 +2 位作者 幸夫诚 陈宇涛 卜祥航 《水利水电快报》 2025年第8期31-39,共9页
为做好四川马尔康地区的滑坡灾害预防工作,针对2022年6月10日马尔康市接连发生的Ms5.8级、Ms6.0级、Ms5.2级地震所引发的滑坡灾害,建立了基于四川省历史地震数据的数据库,运用FCNN模型对此次震群诱发的滑坡空间分布进行分析,并提取马尔... 为做好四川马尔康地区的滑坡灾害预防工作,针对2022年6月10日马尔康市接连发生的Ms5.8级、Ms6.0级、Ms5.2级地震所引发的滑坡灾害,建立了基于四川省历史地震数据的数据库,运用FCNN模型对此次震群诱发的滑坡空间分布进行分析,并提取马尔康境内主要水电站流域,进行滑坡易发性分析。结果表明:①68.56%的滑坡落入极高、高易发区,与卫星影像解译滑坡的结果相符;②此次地震引发的滑坡灾害数量庞大、分布广泛、规模不均,主要集中在松岗断裂带北侧和龙子坝断裂带西北侧,地形起伏为36~107 m,坡度为16°~48°;③脚木足河、茶堡河水电站流域均为滑坡高度发育区,盘龙河水电站流域上游为滑坡高度发育区,下游处于中低易发区域,区域内滑坡受水力侵蚀、地形变化的强烈控制;④将FCNN模型预测结果与影像解译、地质灾害现场调查数据对比,验证了模型预测准确率达75%以上。研究成果对马尔康地区滑坡灾害的监测与防控具有理论与工程实践参考价值。 展开更多
关键词 地震群 同震滑坡 空间分布 FCNN模型 水电站流域 四川省 马尔康
在线阅读 下载PDF
福美钠除重金属的应用研究进展
6
作者 陈春霞 张立 +3 位作者 向瀚 张震 王娟娟 王建伟 《化工环保》 北大核心 2025年第4期481-487,共7页
福美钠是一种重要的化工产品,在工业废水处理、电解锰生产、飞灰稳定化、湿法冶炼、矿石浮选等领域具有广泛的应用。本文对福美钠的合成工艺、检测方法、除重金属机理及不同应用场景下的应用效果进行了归纳总结。作为重金属螯合剂,福美... 福美钠是一种重要的化工产品,在工业废水处理、电解锰生产、飞灰稳定化、湿法冶炼、矿石浮选等领域具有广泛的应用。本文对福美钠的合成工艺、检测方法、除重金属机理及不同应用场景下的应用效果进行了归纳总结。作为重金属螯合剂,福美钠配位能力强,可与多种重金属离子生成稳定的重金属螯合沉淀物。在矿石浮选中,福美钠能有效抑锌浮铜,实现铜锌矿物的分离。目前对于福美钠产品尚无对口的国家和行业标准,亟需制定相关标准来填补空白,并开展产品检测方法的研发工作。 展开更多
关键词 福美钠 二硫代氨基甲酸盐 重金属螯合剂 抑制剂
在线阅读 下载PDF
High-performance room temperature solid-state lithium battery enabled by PP-PVDF multilayer composite electrolyte
7
作者 Sheng Zhao Junjie Lu +4 位作者 Bifu Sheng Siying Zhang Hao Li Jizhang Chen xiang han 《Chinese Chemical Letters》 2025年第6期729-732,共4页
Solid-state batteries(SSBs)with thermal stable solid-state electrolytes(SSEs)show intrinsic capacity and great potential in energy density improvement.SSEs play critical role,however,their low ionic conductivity at ro... Solid-state batteries(SSBs)with thermal stable solid-state electrolytes(SSEs)show intrinsic capacity and great potential in energy density improvement.SSEs play critical role,however,their low ionic conductivity at room temperature and high brittleness hinder their further development.In this paper,polypropylene(PP)-polyvinylidene fluoride(PVDF)-Li_(1.3)Al_(0.3)Ti_(1.7)(PO_(4))_(3)(LATP)-Lithium bis(trifluoromethane sulphonyl)imide(LiTFSI)multi-layered composite solid electrolyte(CSE)is prepared by a simple separator coating strategy.The incorporation of LATP nanoparticle fillers and high concentration LiTFSI not only reduces the crystallinity of PVDF,but also forms a solvation structure,which contributes to high ionic conductivity in a wide temperature.In addition,using a PP separator as the supporting film,the mechanical strength of the electrolyte was improved and the growth of lithium dendrites are effectively inhibited.The results show that the CSE prepared in this paper has a high ionic conductivity of 6.38×10^(-4)S/cm at room temperature and significantly improves the mechanical properties,the tensile strength reaches 11.02 MPa.The cycle time of Li/Li symmetric cell assembled by CSE at room temperature can exceed 800 h.The Li/LFP full cell can cycle over 800 cycles and the specific capacity of Li/LFP full cell can still reach 120 m Ah/g after 800 cycles at 2 C.This CSE has good cycle stability and excellent mechanical strength at room temperature,which provides an effective method to improve the performance of solid electrolytes under moderate condition. 展开更多
关键词 Lithium-ion batteries Composite solid electrolyte Interface stability Mechanical properties Room temperature cycling
原文传递
Carbon interconnected microsized Si film toward high energy room temperature solid-state lithium-ion batteries
8
作者 Xin Li Ling Zhang +10 位作者 Yunyan Fan Shaojing Lin Yong Lin Yongsheng Ying Meijiao Hu Haiying Gao Xianri Xu Zhongbiao Xia Xinchuan Lin Junjie Lu xiang han 《Chinese Chemical Letters》 2025年第2期503-507,共5页
Solid-state batteries(SSBs)with high-capacity Si anodes have been regarded as one of the most promising candidates to meet the large scale energy storage and electrical vehicles due to its intrinsic safety and potenti... Solid-state batteries(SSBs)with high-capacity Si anodes have been regarded as one of the most promising candidates to meet the large scale energy storage and electrical vehicles due to its intrinsic safety and potential high energy density.However,Si suffers from poor electrical conductivity and huge volume change and particles fracture during lithiaiotn and delithiation,which induces low practical energy density.In addition,the SSBs are often operated at high temperature due to the poor physical contact and huge resistance between Si and solid-state electrolyte(SSE).To improve the bulk electronic/ionic conductivity of Si and its interfacial compatibility with SSE,herein,a binder free and self-supporting Si/C film was developed.The monolithic carbon not only enhance the electric conductivity but also release huge stress during lithiation and delithiation.In addition,paired with the flexible and soft poly(vinylidene fluoride)-co-hexafluoropropylene(PVDF-HFP)and Li_(1.3)A_(l0.3)Ti_(1.7)(PO_(4))_(3)(LATP)solid-state electrolyte,a LiF-rich and electrochemical stable solid-electrolyte interphase(SEI)layer is in-situ engineered.The fast bulk and interfacial ionic transportation as well as the mechanical integrity of MSi enable high performance SSBs at room temperature.As a result,high specific capacity of 2137 m Ah/g with an initial Coulombic efficiency of 83.2%is obtained at a rate of 0.5 A/g.Even at a high rate of 3 A/g,the specific capacity is1793 m Ah/g.At a rate of 1 A/g,the Si/C anode delivers a long cycling performance over 500 cycles while maintains a capacity of 1135 mAh/g.This work provides a new strategy that combines charge transfer kinetics and interfacial chemistry design toward high energy density Si-based SSBs. 展开更多
关键词 Lithium-ion battery Solid-state electrolyte Silicon anode Carbon coating INTERPHASE
原文传递
Charge polarity inversion and zincophilicity improvement for chitosan separator towards durable aqueous zinc-ion batteries
9
作者 Jiaqi Yu Bo Liu +4 位作者 Hong Ma Zehua Fan xiang han Qinghua Tian Jizhang Chen 《Journal of Energy Chemistry》 2025年第2期110-119,I0004,共11页
Aqueous zinc-ion batteries encounter enormous challenges such as Zn dendrites and parasitic reactions.Separator modification is a highly effective strategy to address these issues.With the advantages of low cost,nonto... Aqueous zinc-ion batteries encounter enormous challenges such as Zn dendrites and parasitic reactions.Separator modification is a highly effective strategy to address these issues.With the advantages of low cost,nontoxicity,biodegradability,good film-forming ability,superior hydro phi licity,and rich functional groups,chitosan is an ideal matrix for constructing separators.However,the presence of positive charges within chitosan in weakly acidic electrolytes is unfavorable for dendrite inhibition.Herein,Schiff base reaction is introduced to modify chitosan matrix,transforming its charge polarity from positive to negative.Additionally,NbN with excellent zincophilicity is coated onto chitosan matrix,forming a Janus separator with low thickness of 19μm and considerably improved mechanical properties.The resultant separator can promote the transport of Zn^(2+)ions while triggering a repulsive shielding effect against anions,therefore dramatically enhancing Zn^(2+)ion transfer number from 0.28 to 0.49.This separator can also facilitate desolvation process,improve exchange current density,restrict two-dimensional Zn^(2+)ion diffusion,and enhance electrochemical kinetics,contributing to significantly inhibited dendrite growth,by-product formation,and hydrogen evolution.Consequently,stable and reversible Zn stripping/plating process is enabled for over 2500 h at 2 mA cm^(-2)and 2 mAh cm^(-2).And great rate capability and excellent cyclability can be achieved for full batteries even under harsh conditions.This work provides new insights into separator design for Zn-based batteries. 展开更多
关键词 Separator modification Charge polarity regulation Dendrite inhibition Aqueous zinc-ion batteries Chitosan utilization
在线阅读 下载PDF
Molten salts assisted synthesis of single crystalline NCM811 with surface modification for high energy density lithium-ion batteries
10
作者 Bi-Fu Sheng Jun-Jie Lu +9 位作者 Zhe-Fei Sun Min-Feng Chen Min Xu han-Rui Zhao Qing-Qing Zhou Chu-Yang Li Bin Wang Qiao-Bao Zhang Ji-Zhang Chen xiang han 《Rare Metals》 2025年第6期3749-3760,共12页
Single crystalline nickel rich Li[Ni_(x)Co_(y)Mn_(1-x–y)]O_(2)(SCNCM)layered oxide cathodes show higher ionic conductivity and better structure integrity than polycrystalline NCM(PCNCM)cathodes by eliminating grain b... Single crystalline nickel rich Li[Ni_(x)Co_(y)Mn_(1-x–y)]O_(2)(SCNCM)layered oxide cathodes show higher ionic conductivity and better structure integrity than polycrystalline NCM(PCNCM)cathodes by eliminating grain boundaries.However,it remains challenges in the controlled synthesis process and restricted cycling stability of SCNCM.Herein,take single crystalline nickel rich Li[Ni_(0.8)Co_(0.1)Mn_(0.1)]O_(2)(SC811)as an example,a dual molten salts(LiOH and Li_(2)SO_(4))assisted secondary calcination method is proposed,for which LiOH salt improves primary crystal size and Li_(2)SO_(4)prevents the aggravation of NCM nanocrystals.To further reduce the interfacial side reactions,Mg-doping and B-coating surface modification was carried out,which effectively suppress anisotropic lattice changes and Li/Ni disorder.In addition,a thin and uniform H_(3)BO_(3)coating effectively prevents direct contact between the electrode and electrolyte,thus reducing harmful parasitic reactions.The single crystal structure engineering and surface modification strategy of oxide layered cathodes significantly improve the cycling stability of the modified SC811 cathode.For example,during a long-term cycling of 470 cycles,a high-capacity retention of 74.2%obtained at 1C rate.Our work provides a new strategy for engineering high energy nickel rich layered oxide NCM cathodes. 展开更多
关键词 Lithium-ion battery Nickel rich cathode Molten salts Surface modification
原文传递
超微创腹腔镜胆囊切除术
11
作者 黄英杰 向涵 +1 位作者 汪鑫 张伟 《手术电子杂志》 2025年第4期19-21,共3页
胆囊切除术是治疗良性胆囊疾病最有效的办法。腹腔镜下胆囊切除术已经成为胆囊切除术的标准术式。随着微创外科理念的发展,手术方式逐渐由“微创”向“无痕化”方向发展。单孔腹腔镜胆囊切除术相较于传统三孔法在腹壁美观度、术后切口... 胆囊切除术是治疗良性胆囊疾病最有效的办法。腹腔镜下胆囊切除术已经成为胆囊切除术的标准术式。随着微创外科理念的发展,手术方式逐渐由“微创”向“无痕化”方向发展。单孔腹腔镜胆囊切除术相较于传统三孔法在腹壁美观度、术后切口疼痛程度等方面均有明显优势。然而,单孔腹腔镜胆囊切除术因操作难度大(筷子效应明显)、手术时间较长等问题,其发展受到一定的限制。为解决单孔腹腔镜手术操作难度大等问题。根据腹壁切口<2 mm时不会形成明显疤痕的临床研究结论,笔者团队使用直径1.4 mm的超微创牵拉装置(T型线)及直径1.98 mm的超微创钳辅助完成单孔手术。解决单孔手术难题的同时,拥有单孔手术的效果。笔者团队将脐部切口数量控制在不超过两个,且最大直径不超过15 mm,其余腹部切口直径均<2 mm,保证切口隐藏于脐部自然凹陷内的手术方式命名为“超微创腹腔镜手术(SMLS)”。以此种手术方式进行的胆囊切除术为“超微创腹腔镜胆囊切除术(SMLC)”。 展开更多
关键词 超微创 腹腔镜 胆囊切除术
暂未订购
Neuroprotective mechanism of TMP269, a selective class ⅡA histone deacetylase inhibitor, after cerebral ischemia/reperfusion injury 被引量:5
12
作者 Lu Su Dan Liang +3 位作者 Shen-Yi Kuang Qiang Dong xiang han Zheng Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第2期277-284,共8页
TMP269 is a selective class ⅡA histone deacetylase inhibitor that has a protective effect on the central nervous system, whose specific mechanism of action is unclear. We aimed to reveal the optimal concentration of ... TMP269 is a selective class ⅡA histone deacetylase inhibitor that has a protective effect on the central nervous system, whose specific mechanism of action is unclear. We aimed to reveal the optimal concentration of TMP269 for protecting against cerebral ischemia/reperfusion injury and its neuroprotective mechanism. Male Sprague-Dawley rats were randomly divided into sham, ischemia/reperfusion, and 1, 4, 10 and 16 mg/kg TMP269 groups. Cerebral ischemia/reperfusion injury was induced by middle cerebral artery occlusion. TMP269 was intraperitoneally administered at different doses 0.5 hours before ischemia induction. Western blot assay and immunohistochemistry were used to detect effects of TMP269 on histone 2 acetylation. The results showed that the level of histone 2 acetylation was increased 24 hours after TMP269 injection. 2,3,5-Triphenyltetrazolium chloride staining was utilized to examine effect of TMP269 on infarct volume. The results found that different doses of TMP269 could reduce the infarct volume. Western blot assay, immunohistochemistry and Evans blue staining were employed to measure the effect of TMP269 on blood-brain barrier. The results showed that TMP269 counteracted the abnormal endothelial cell permeability changes caused by cerebral ischemia/reperfusion. Western blot assay and immunohistochemistry were used to determine the effect of TMP269 on tissue kallikrein. The results found that TMP269 up-regulated the expression of tissue kallikrein. Western blot assay further determined the optimal concentration to be 4 mg/kg. In conclusion, TMP269 plays a neuroprotective role by up-regulating the level of histone 2 acetylation, alleviating endothelial cell injury after cerebral ischemia/reperfusion, and up-regulating the expression of tissue kallikrein. The experimental protocol was approved in 2014 by the Department of Laboratory Animal Science, Fudan University, China(approval No. 20140143 C001). 展开更多
关键词 blood-brain barrier drug treatment ENDOTHELIAL cell permeability HISTONE DEACETYLASE inhibitor NEUROPROTECTION stroke tissue KALLIKREIN TMP269
暂未订购
条带充填绿色开采回收压覆煤炭资源支巷宽度研究 被引量:2
13
作者 陈全秋 项瀚 赵宝友 《煤炭工程》 北大核心 2024年第9期14-20,共7页
以山西三元煤业3号煤条带充填工作面为工程背景,基于固支梁理论模型,分析了条带充填开采支巷顶板的变形与受力特征;并采用数值模拟方法揭示了循环间隔条带充填开采支巷间的相互作用及支巷围岩的塑性区分布特征,综合理论解析研究结果并... 以山西三元煤业3号煤条带充填工作面为工程背景,基于固支梁理论模型,分析了条带充填开采支巷顶板的变形与受力特征;并采用数值模拟方法揭示了循环间隔条带充填开采支巷间的相互作用及支巷围岩的塑性区分布特征,综合理论解析研究结果并结合三元煤业充填工作面实际条件,确定多轮循环间隔条带充填开采支巷的合理宽度为5 m;最后,通过工程实践验证了支巷宽度的合理性,实现了压覆煤炭资源的安全采出,促进了三元煤业的绿色可持续开采。 展开更多
关键词 压覆煤炭资源 条带充填 绿色开采 固支梁 支巷宽度
在线阅读 下载PDF
三峡库区(重庆段)乡村地名文化景观的空间分布特征及成因 被引量:4
14
作者 刘庆果 孙丕苓 +2 位作者 王世清 向罕 王松梅 《山地学报》 CSCD 北大核心 2024年第1期108-122,共15页
地名体现鲜明的地方特色,承载丰富的文化内涵。开展乡村地名研究对多民族融合地区的乡土文化传承具有重要的现实意义。目前多民族融合的水系流域乡村地名空间分布特征及影响因素研究相对较为缺乏。本文以三峡库区(重庆段)乡村地名为研... 地名体现鲜明的地方特色,承载丰富的文化内涵。开展乡村地名研究对多民族融合地区的乡土文化传承具有重要的现实意义。目前多民族融合的水系流域乡村地名空间分布特征及影响因素研究相对较为缺乏。本文以三峡库区(重庆段)乡村地名为研究对象,综合运用数理统计、平均最邻近距离、核密度估计法分析其空间分布特征及成因。研究表明:(1)乡村地名分布呈现空间集聚特征。自然景观类乡村地名密度呈现东北和西南高、中部低的空间格局;以地形、水文、生物等命名的乡村地名主要分布于库区东北部山区及西南部海拔较低的平坦地区;地理方位类和颜色类乡村地名主要呈点状分布。(2)人文景观类乡村地名集聚分布范围较广且空间差异明显。数字类和人工建筑类乡村地名主要分布于库区东北部山区及西南部城区;军事活动类和历史政治类乡村地名集聚于西南部海拔较低的主城区;姓氏类和园林景观类乡村地名集中分布于东北部山区;美愿与纪念类和多民族文化类乡村地名空间分布基本一致。(3)乡村地名是地形地貌、水文特征、生物资源、经济发展、历史传承、民族文化等因素共同作用的产物。该研究可为三峡库区的多民族融合发展、乡土文化传承等研究提供科学参考。 展开更多
关键词 乡村地名 空间分布 平均最近邻指数 核密度估计 三峡库区 重庆
在线阅读 下载PDF
Experimental study of core MHD behavior and a novel algorithm for rational surface detection based on profile reflectometry in EAST
15
作者 叶凯萱 周振 +20 位作者 张涛 马九阳 王嵎民 李恭顺 耿康宁 吴茗甫 文斐 黄佳 张洋 邵林明 杨书琪 钟富彬 高善露 喻琳 周子强 向皓明 韩翔 张寿彪 李国强 高翔 the EAST Team 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第3期66-75,共10页
Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasm... Microwave reflectometry is a powerful diagnostic that can measure the density profile and localized turbulence with high spatial and temporal resolution and will be used in ITER,so understanding the influence of plasma perturbations on the reflect signal is important.The characteristics of the reflect signal from profile reflectometry,the time-of-flight(TOF)signal associated with the MHD instabilities,are investigated in EAST.Using a 1D full-wave simulation code by the Finite-DifferenceTime-Domain(FDTD)method,it is well validated that the local density flattening could induce the discontinuity of the simulated TOF signal and an obvious change of reflect amplitude.Experimental TOF signals under different types of MHD instabilities(sawtooth,sawtooth precursors and tearing mode)are studied in detail and show agreement with the simulation.Two new improved algorithms for detecting and localizing the radial positions of the low-order rational surface,the cross-correlation and gradient threshold(CGT)method and the 2D convolutional neural network approach(CNN)are presented for the first time.It is concluded that TOF signal analysis from profile reflectometry can provide a straightforward and localized measurement of the plasma perturbation from the edge to the core simultaneously and may be a complement or correction to the q-profile control,which will be beneficial for the advanced tokamak operation. 展开更多
关键词 MHD instabilities profile reflectometry rational surface detection convolutional neural network(CNN) EAST tokamak
在线阅读 下载PDF
毛竹笋木聚糖提取工艺优化及其抗氧化活性分析
16
作者 陈甘霖 李兰兰 +3 位作者 林平东 向韩 付蕾 吴允昆 《福建农业科技》 CAS 2024年第7期62-68,共7页
为了实现竹笋加工废弃物的资源转化与利用,采用碱提醇沉法提取毛竹笋中的木聚糖,通过单因素试验和正交试验优化提取工艺,利用高效液相色谱法和傅里叶变换红外光谱分析毛竹笋木聚糖的理化性质,并通过DPPH法和ABTS法评价毛竹笋木聚糖的体... 为了实现竹笋加工废弃物的资源转化与利用,采用碱提醇沉法提取毛竹笋中的木聚糖,通过单因素试验和正交试验优化提取工艺,利用高效液相色谱法和傅里叶变换红外光谱分析毛竹笋木聚糖的理化性质,并通过DPPH法和ABTS法评价毛竹笋木聚糖的体外抗氧化活性。结果表明:在提取时间3.5 h、碱液质量浓度0.1 g·mL^(−1)、料液比1∶25,提取温度100℃的条件下,毛竹笋木聚糖提取率最高,可达20.86%。单糖组成和FT-IR分析表明木糖可能是构成毛竹笋木聚糖的主要成分。体外抗氧化性试验表明毛竹笋木聚糖具有一定的抗氧化活性,当浓度为8 mg·mL^(−1)时,其对DPPH自由基的清除率达到94.75%,IC_(50)值为1.0 mg·mL^(−1);当浓度为20 mg·mL^(−1)时,其对ABTS自由基的清除率为93.09%,IC_(50)值为3.85 mg·mL^(−1)。 展开更多
关键词 毛竹笋 木聚糖 提取工艺 抗氧化活性
在线阅读 下载PDF
中国共产党历史主动精神的形成机理、内在意蕴与时代价值
17
作者 郭国祥 向涵 《湖北行政学院学报》 2024年第2期76-83,共8页
历史主动精神是中国共产党宝贵的精神品质,其生成具有深刻的内在逻辑:源自对马克思主义唯物史观的运用与发展,源自对中华优秀传统文化的萃取与升华,源自对党的百年奋斗历史经验的深刻总结。历史主动精神具有丰富的思想内涵,蕴含着遵循... 历史主动精神是中国共产党宝贵的精神品质,其生成具有深刻的内在逻辑:源自对马克思主义唯物史观的运用与发展,源自对中华优秀传统文化的萃取与升华,源自对党的百年奋斗历史经验的深刻总结。历史主动精神具有丰富的思想内涵,蕴含着遵循历史规律的科学精神,尊重人民群众的首创精神,直面风险挑战的斗争精神,坚守初心使命的担当精神。新时代新征程,历史主动精神蕴含重大的时代价值,是锻造走在时代前列的马克思主义执政党的精神指引,是深入推进中国式现代化道路的精神动力,是应对世界百年未有之大变局的精神武器。 展开更多
关键词 中国共产党 历史主动精神 党的二十大
在线阅读 下载PDF
精细化管理在达芬奇机器人手术器械再处理质量控制中的应用效果
18
作者 娄静 项晗 +2 位作者 张如萍 张文华 苏钰斌 《中西医结合护理(中英文)》 2024年第11期136-138,共3页
目的探讨精细化管理模式对达芬奇机器人手术器械再处理质量的影响。方法以2022年10月至2023年3月徐州医科大学附属医院消毒供应中心回收的180件达芬奇机器人手术器械作为研究对象。按管理模式的不同分为对照组(常规管理)和观察组(精细... 目的探讨精细化管理模式对达芬奇机器人手术器械再处理质量的影响。方法以2022年10月至2023年3月徐州医科大学附属医院消毒供应中心回收的180件达芬奇机器人手术器械作为研究对象。按管理模式的不同分为对照组(常规管理)和观察组(精细化管理),各90件。比较2组的器械再处理质量、器械周转时间、风险事件发生率及器械使用满意率。结果观察组的器械交接正确率、预处理合格率、清洗合格率、包装合格率和器械使用总满意率均高于对照组,器械周转时间短于对照组,器械功能损坏、部件丢失、信息追溯环节不完整的风险事件总发生率低于对照组(P均<0.05)。结论精细化管理可提升达芬奇机器人手术器械的再处理质量和使用满意度,缩短器械周转时间,降低风险事件发生率。 展开更多
关键词 器械再处理 达芬奇机器人 精细化管理 质量控制 器械周转时间
暂未订购
项目内部排污系统设计要点及分析
19
作者 向晗 《城市建筑》 2024年第8期229-232,共4页
在城市更新过程中,产生大量项目地块内部污水管道建设任务。这部分污水管道是城市污水管网系统的源头,其质量管控和运行效果既关系城市污水收集率,又影响城市水环境治理效果,加之设计对项目建设具有引领作用,所以必须重视并抓好项目内... 在城市更新过程中,产生大量项目地块内部污水管道建设任务。这部分污水管道是城市污水管网系统的源头,其质量管控和运行效果既关系城市污水收集率,又影响城市水环境治理效果,加之设计对项目建设具有引领作用,所以必须重视并抓好项目内部污水管道的方案设计工作,并将其作为后续工程质量管控的依据。 展开更多
关键词 项目内部污水管道 设计 雨污分流 检查井
在线阅读 下载PDF
91%杀螺胺乙醇胺盐可湿性粉剂的研制 被引量:2
20
作者 赵磊 项汉 +2 位作者 任帅臻 李成浩 任天瑞 《世界农药》 CAS 2018年第2期48-50,53,共4页
为解决杀螺胺乙醇胺盐可湿性粉剂使用过程中絮凝、变色问题,通过试验筛选润湿分散剂等进行组合优化,确定了91%杀螺胺乙醇胺盐的可湿性粉剂的最佳配方:杀螺胺乙醇胺盐原药91%,分散剂SD-819为1%、SD-720为5.5%,润湿剂wet-88为0.5%,抗絮凝... 为解决杀螺胺乙醇胺盐可湿性粉剂使用过程中絮凝、变色问题,通过试验筛选润湿分散剂等进行组合优化,确定了91%杀螺胺乙醇胺盐的可湿性粉剂的最佳配方:杀螺胺乙醇胺盐原药91%,分散剂SD-819为1%、SD-720为5.5%,润湿剂wet-88为0.5%,抗絮凝剂三聚磷酸钠1%,白炭黑为填料补足。结果表明,所得制剂无絮凝变色,热贮稳定且悬浮率大于90%,,各项指标均符合可湿性粉剂质量要求。 展开更多
关键词 91%杀螺胺乙醇胺盐 配方 絮凝 变色
在线阅读 下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部