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Noether Symmetry Can Lead to Non-Noether Conserved Quantity of Holonomic Nonconservative Systems in General Lie Transformations

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Communications in Theoretical Physics 2005年第2期43卷 193-196页

作者： LUOShao-Kai jiali-qun CAIJian-Le InstituteofMathematicalMechanicsandMathematicalPhysics ZhejiangSci-TechUnivcrsityHangzhou310018China／／InstituteofMathematicalMechanicsandMathematicalPhysicsChangshaUniversityChangsha410003China ScienceCollegeofSouthern YangtzeUniversityWuxi214063China DepartmentofPhysics HangzhouTeachersCollegeHangzhou310018China

For the holonomic nonconservative system, by using the Noether symmetry, a non-Noether conserved quantity is obtained directly under general infinitesimal transformations of groups in which time is variable. At first,the Noether symmetry, Lie symmetry, and Noether conserved quantity are given. Secondly, the condition under which the Noether symmetry is a Lie symmetry under general infinitesimal transformations is obtained. Finally, a set of nonNoether conserved quantities of the system are given by the Noether symmetry, and an example is given to illustrate the application of the results.

关键词： holonomic conservative system noether symmetry non-Noether conservedquantity general inifinitesimal transformations of groups

Bioaccumulation characterization of uranium by a novel Streptomyces sporoverrucosus dwc-3

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Journal of Environmental Sciences 2016年第3期28卷 162-171页

作者： Xiaolong Li Congcong Ding jiali Liao Liang Du qun Sun Jijun Yang Yuanyou Yang Dong Zhang Jun Tang Ning Liu Key Laboratory of Radiation Physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan University Key Laboratory of Biological Resource and Ecological Environment of the Ministry of Education College of Life SciencesSichuan University Institute of Nuclear Physics and Chemistry CAEP

The biosorption mechanisms of uranium on an aerobic bacterial strain Streptomyces sporoverrucosus dwc-3,isolated from a potential disposal site for（ultra-）low uraniferous radioactive waste in Southwest China,were evaluated by using transmission electron microscopy（TEM）,energy dispersive X-ray（EDX）analysis,Fourier transform infrared spectroscopy（FT-IR）,X-ray photoelectron spectroscopy（XPS）,proton induced X-ray emission（PIXE）and enhanced proton backscattering spectrometry（EPBS）.Approximately60% of total uranium at an initial concentration of 10 mg/L uranium nitrate solution could be absorbed on 100 mg *** dwc-3 with an adsorption capacity of more than3.0 mg/g（wet weight）after 12 hr at room temperature at p H *** dynamic biosorption process of *** dwc-3 for uranyl ions was well described by a pseudo second-order *** dwc-3 could accumulate uranium on cell walls and within the cell,as revealed by SEM and TEM analysis as well as EDX *** and FT-IR analysis further suggested that the absorbed uranium was bound to amino,phosphate and carboxyl groups of the ***,PIXE and EPBS results confirmed that ion exchange also contributed to the adsorption process of uranium.

关键词： Bioaccumulation Uranium Nanoparticle Streptomyces sporoverrucosus dwc-3 Bioremediation

Microbial reduction of uranium(Ⅵ)by Bacillus ***-2:A macroscopic and spectroscopic study

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Journal of Environmental Sciences 2017年第3期29卷 9-15页

作者： Xiaolong Li Congcong Ding jiali Liao Liang Du qun Sun Jijun Yang Yuanyou Yang Dong Zhang Jun Tang Ning Liu Key Laboratory of Radiation Physics and Technology Ministry of EducationInstitute of Nuclear Science and TechnologySichuan UniversityChengdu 610064China Institute of Nuclear Physics and Chemistry CAEPMianyang 621900China Key Laboratory of Biological Resource and Ecological Environment of the Ministry of Education College of Life SciencesSichuan UniversityChengdu 610064China

The microbial reduction of U（VI） by Bacillus sp. dwc-2, isolated from soil in Southwest China, was explored using transmission electron microscopy （TEIVI）, X-ray photoelectron spectros- copy （XPS） and X-ray absorption near edge spectroscopy （XANES）. Our studies indicated that approximately 16.0% of U（VI） at an initial concentration of 100 mg/L uranium nitrate could be reduced by Bacillus sp. dwc-2 at pH 8.2 under anaerobic conditions at room temperature. Additionally, natural organic matter （NOM） played an important role in enhancing the bioreduction of U（VI） by Bacillus sp. dwc-2. XPS results demonstrated that the uranium presented mixed valence states （U（VI） and U（IV）） after bioreduction, which was subse- quently confirmed by XANES. Furthermore, the TEM and high resolution transmission electron microscopy （HRTEM） analysis suggested that the reduced uranium was bioaccumulated mainly within the cell and as a crystalline structure on the cell wa11. These observations implied that the reduction of uranium may have a significant effect on its fate in the soil environment in which these bacterial strains occur.

关键词： Uranium BioreductionBacillus sp. dwc-2Nanoparticle

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网络地位、共享商业关系与大客户占比

经济研究 2021年第10期56卷 189-205页

作者：包群但佳丽南开大学经济学院国际经济与贸易系 300071

与传统商业关系相比,日益复杂的现代商业网络使企业能够更好地拓展新客户关系,从而缓解过度依赖单一客户关系的商业风险。本文基于2009—2017年上市公司数据,考察了企业网络地位与结构对商业关系的影响,研究发现:与位于网络边缘地位的... 详细信息

与传统商业关系相比,日益复杂的现代商业网络使企业能够更好地拓展新客户关系,从而缓解过度依赖单一客户关系的商业风险。本文基于2009—2017年上市公司数据,考察了企业网络地位与结构对商业关系的影响,研究发现:与位于网络边缘地位的企业相比,核心企业更有可能利用网络优势来分散客户市场份额,但同时位于核心位置的商业伙伴也越难以被替代;基于客户-供应商网络的共享商业关系、商业搜寻效率均有助于企业进行商业关系分散化,这一作用当共享联系越为紧密、共享相似度越高时更为显著,但现有客户可替代性越低、商业关系持续时间越长会增大分散化难度;网络地位和结构从商业关系的集约边际和扩展边际影响着企业分散商业风险的能力。本文研究证实了现代商业网络有助于促进企业商业关系的分散化,以更为灵活地防范市场环境不确定性的经营风险。

关键词：网络地位共享商业关系市场风险分散

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国内贸易网络、地理距离与供应商本地化

经济研究 2023年第6期58卷 102-118页

作者：包群但佳丽王云廷南开大学经济学院国际经济与贸易系 300071

灵活、有效的供应商关系管理对企业正常运行具有关键意义。以上市公司总部搬迁为冲击,本文考察了总部迁移之后供应商地理分布的调整反应。通过内生供应商选择决策,本文理论研究发现,总部迁移后供应商更替决策取决于新供应商搜寻成本与... 详细信息

灵活、有效的供应商关系管理对企业正常运行具有关键意义。以上市公司总部搬迁为冲击,本文考察了总部迁移之后供应商地理分布的调整反应。通过内生供应商选择决策,本文理论研究发现,总部迁移后供应商更替决策取决于新供应商搜寻成本与旧供应商维系成本的权衡比较。基于2001—2017年间中国上市公司的供应商-客户匹配数据,本文实证结果发现:(1)总部搬迁企业的确更有可能发生供应关系变更,且这一效果在远距离搬迁中更为显著。(2)新供应关系搜寻效率越高,企业越有可能替换原有贸易伙伴;与旧贸易伙伴的关系粘性越低,供应关系更替概率也越高;对中间投入品供应商依赖度低的企业也更可能更换新供应商。(3)由于贸易伙伴选择依赖于地理距离的远近,导致供应关系呈现出高度本地化现象。本文研究揭示了在经营环境不确定性风险加剧时供应关系及时调整的重要性。

关键词：国内贸易网络搜寻效率维系成本

外资身份的重要性:基于外资股权限定的经验分析

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世界经济 2020年第7期43卷 73-97页

作者：包群但佳丽张志强南开大学经济学院国际经济与贸易系南开大学经济学院城市与区域经济研究所

与东道国当地企业相比,外资企业享受着税收优惠等超国民待遇,导致难以断定外资绩效优势究竟来自企业自身竞争能力,还是仅仅体现了特殊身份收益。基于商务部制订的25%外资股权身份认定门槛,本文发现:外资优惠政策激励导致企业分布失衡的... 详细信息

与东道国当地企业相比,外资企业享受着税收优惠等超国民待遇,导致难以断定外资绩效优势究竟来自企业自身竞争能力,还是仅仅体现了特殊身份收益。基于商务部制订的25%外资股权身份认定门槛,本文发现:外资优惠政策激励导致企业分布失衡的典型事实,25%股权右侧区域企业数目是左侧对照组的3倍多,且主要体现在引资鼓励类行业;在股权比例20%-30%范围内的企业,虽然外资企业在税收优惠、销售业绩、流动性等经营绩效表现更好,但在生产率方面却无显著差异;地区与行业引资优惠政策是导致外资分布失衡的重要原因;以2007年“内外资两税合一”为准自然实验的研究发现,取消所得税优惠之后,企业不再偏好更高的外资股权比例。本文研究表明外资身份受益主要体现在税收优惠方面,但对企业生产率的影响有限,而且这一吸引力在外资优惠取消之后逐渐减弱。

关键词：外资身份引资优惠机器学习

固废基气凝胶粒子电极的制备及电催化降解有机污染物的性能与机制

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高等学校化学学报 2024年第10期45卷 57-68页

作者：李赟李红艳张峰肖子君王芳崔佳丽杨群太原理工大学环境科学与工程学院山西省市政工程研究生教育创新中心晋中030600 吕梁学院建筑与土木工程系吕梁033001 哈尔滨工业大学环境学院城市水资源与水环境国家重点实验室哈尔滨150090 山西省生物研究院有限公司食用菌研究中心太原030006 黄土高原食用菌山西省重点实验室太谷030801

以废菌棒(MS)和赤泥(RM)为原料,经过煅烧得到粉末状废菌棒赤泥生物炭(MSRMBC).采用悬浮滴定CaCl_(2)法以海藻酸钠(SA)为骨架的凝胶对MSRMBC进行包埋制得气凝胶粒子电极(MSRMBC@SA),并利用扫描电子显微镜(SEM)、能量色散谱(EDS)、傅里叶... 详细信息

以废菌棒(MS)和赤泥(RM)为原料,经过煅烧得到粉末状废菌棒赤泥生物炭(MSRMBC).采用悬浮滴定CaCl_(2)法以海藻酸钠(SA)为骨架的凝胶对MSRMBC进行包埋制得气凝胶粒子电极(MSRMBC@SA),并利用扫描电子显微镜(SEM)、能量色散谱(EDS)、傅里叶变换红外光谱(FTIR)、X射线衍射(XRD)、氮气吸附-脱附实验和循环伏安曲线(CV)对其进行表征分析.利用MSRMBC@SA构建三维电芬顿体系(3D-EFMSRMBC@SA),以卡马西平(CBZ)为模型化合物,考察了MSRMBC@SA投加量、电压、曝气量和pH值对MSRMBC@SA电催化性能的影响,最佳降解条件下CBZ(10 mg/L)的降解率为86.05%.因MSRMBC@SA具有良好的pH值调节能力,故体系受pH值影响较小.自由基猝灭、电子自旋共振(ESR)及X射线光电子能谱(XPS)表征结果表明,·OH为主要活性物种,MSRMBC@SA在CBZ降解过程中起到了关键的催化作用.研究发现,MSRMBC@SA稳定性较好,且3D-EF-MSRMBC@SA较2D-EF及3D-EF-MSRMBC具有更低的能耗和更佳的降解效果.MSRMBC@SA可有效降低CBZ溶液的生物毒性,对实际CBZ抗生素废水降解具有良好的应用前景.

关键词：气凝胶粒子电极高级氧化技术卡马西平三维电芬顿体系降解机理

3D Surface velocity retrieval of mountain glacier using an offset tracking technique applied to ascending and descending SAR constellation data:a case study of the Yiga Glacier

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International Journal of Digital Earth 2019年第6期12卷 614-624页

作者： qun Wang Jinghui Fan Wei Zhou Liqiang Tong Zhaocheng Guo Guang Liu Weilin Yuan Joaquim Joao Sousa Zbigniew Perski School of Land Science and Technology China University of GeosciencesBeijingPeople’s Republic of China Division of Remote Sensing for Environment China Aero Geophysical Survey and Remote Sensing Center for Land and ResourcesBeijingPeople’s Republic of China Key Laboratory of Digital Earth Science Institute of Remote Sensing and Digital EarthChinese Academy of SciencesBeijingPeople’s Republic of China School of Sciences and Technology University of Trás-os-Montes e Alto DouroVila RealPortugal Centre for Robotics in Industry and Intelligent Systems INESC TECPortoPortugal Polish Geological Institute—National Research Institute CracowPoland

COSMO-SkyMed is a constellation of four X-band high-resolution radar satellites with a minimum revisit period of 12 *** satellites can obtain ascending and descending synthetic aperture radar(SAR)images with very similar periods for use in the three-dimensional(3D)inversion of glacier *** this paper,based on ascending and descending COSMO-SkyMed data acquired at nearly the same time,the surface velocity of the Yiga Glacier,located in the jiali County,Tibet,China,is estimated in four directions using an offset tracking technique during the periods of 16 January to 3 February 2017 and 1 February to 19 February *** the geometrical relationships between the measurements and the SAR images,the least square method is used to retrieve the 3D components of the glacier surface velocity in the eastward,northward and upward *** results show that applying the offset tracking technique to COSMO-SkyMed images can be used to derive the true 3D velocity of a glacier’s *** the two periods,the Yiga Glacier had a stable velocity,and the maximum surface velocity,2.4 m/d,was observed in the middle portion of the glacier,which corresponds to the location of the steepest slope.

关键词： Mountain glacier inversion of 3D movement offset tracking SAR constellation data

Fe_(2)O_(3)-CuO/rCG催化降解水中苯并三氮唑的效能与机理

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工业水处理 2024年第9期44卷 118-126页

作者：郭紫瑞李红艳张峰崔佳丽杨群李赟太原理工大学环境科学与工程学院山西晋中030600 山西省市政工程研究生教育创新中心山西晋中030600 临县丰林现代农业发展有限公司山西吕梁033200

以煤矸石(Coal gangue,CG)为原料,通过煅烧、酸浸和金属改性制备铁铜改性煤矸石(Fe_(2)O_(3)-CuO/rCG),对Fe_(2)O_(3)-CuO/rCG的形貌结构进行了表征分析,并研究了Fe_(2)O_(3)-CuO/rCG/H_(2)O_(2)体系对苯并三氮唑(BTA)的降解效能和作用机理。结果表明:改性后Fe_(2)O_(3)-CuO/rCG比表面积和总孔容均明显增加,Fe_(2)O_(3)与CuO成功填充在材料孔隙内部;Fe_(2)O_(3)-CuO/rCG的最佳制备条件为煅烧温度650℃、煅烧时间3 h、金属离子负载浓度0.07 mol/L;Fe_(2)O_(3)-CuO/rCG/H_(2)O_(2)体系降解BTA的最佳条件为BTA质量浓度30 mg/L、Fe_(2)O_(3)-CuO/rCG投加量2 g/L、H_(2)O_(2)浓度7 mmol/L、温度25℃、转速240 r/min,反应2 h时,体系对BTA降解率最高可达94.86%,TOC与TN去除率分别可达87.69%与84.27%;Fe_(2)O_(3)-CuO/rCG耦合类Fenton体系去除BTA的作用机制主要有吸附和催化降解两种,吸附主要有孔隙填充、配体吸附和氢键作用,催化降解过程·OH和^(1)O_(2)为主要活性物种,且^(1)O_(2)占主导地位,Fe^(2+)/Fe^(3+)和Cu^(+)/Cu^(2+)的氧化还原循环加速了类Fenton体系中活性物种的生成。

关键词：煤矸石催化剂吸附催化降解苯并三氮唑

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