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Population dynamics in northwestern China

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China Population and Development Studies 2021年第4期5卷 107-123页

作者： Xueyan Yang Wanxin Li Wen Jing Chezhuo Gao Rui Li yuqi he Institute for Population and Development Studies School of Public Policy and AdministrationXi’an Jiaotong UniversityXi’anChina

This article analyzes the population dynamics in northwestern China from roughly 2010 to *** area’s dynamics showed a slow,stable increase in population size,a stable increase in the population of non-Han ethnic groups,which increased at a more rapidly than the Han population,and population rejuvenation coupled with a population structure that *** biological sex structure fluctuated within a balanced range in northwestern *** advanced in northwestern China,throughout this period,but the area’s level of urbanization is still significantly lower than the average level of urbanization nationally.

关键词： Fertility Ethnic structure Age structure Urbanization Northwestern China

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黄土孔径和持水特性的分形维数研究

西北大学学报（自然科学版） 2022年第3期52卷 416-422页

作者：廖红建刘少华何玉琪孙俊煜西安交通大学人居环境与建筑工程学院陕西西安710049

黄土结构疏松、水敏性强,在水力作用下,易导致强度骤降,水稳性减弱甚至丧失。黄土中水分以自由水、结合水等多种形式存在于土的孔隙中,孔隙的分布特征是决定土中水分存在和变化规律的主要因素。该文基于压力膜仪试验,结合孔径分布的计... 详细信息

黄土结构疏松、水敏性强,在水力作用下,易导致强度骤降,水稳性减弱甚至丧失。黄土中水分以自由水、结合水等多种形式存在于土的孔隙中,孔隙的分布特征是决定土中水分存在和变化规律的主要因素。该文基于压力膜仪试验,结合孔径分布的计算理论,做出了土水特征曲线和孔径的分布曲线,并结合分形理论,以分形维数为孔隙分布规律的评价指标,建立不同工况下黄土的含水状态变化特性与细观孔隙分布特征间的关系。结果表明,土中孔隙越小,分形维数越大,土的含水状态变化越不明显;土的残余含水率与分形维数呈线性相关,残余含水率增高的同时,分形维数和土体的持水能力也增大;土的进气值与分形维数呈正相关,但不呈线性关系;土中的大孔隙越多,土的进气值就越大,分形维数越大。

关键词：非饱和黄土孔径分布分形理论持水特性

Furin Enzyme-Responsive siRNA Delivery System for Efficient Anti-Hypoxia-Assisted Cancer Photodynamic Therapy

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CCS Chemistry 2024年第4期6卷 999-1010页

作者： Shuyue Ye Yali Feng yuqi Zhang Jing Fang Anna Wang Chaoxiang Cui Jinfeng Zhu Liangsheng Guo Guohua Fan Haibin Shi State Key Laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou 215123 Department of Radiology The Second Affiliated Hospital of Soochow UniversitySuzhou 215004 Department of Obstetrics and Gynecology The Second Affiliated Hospital of Soochow UniversitySuzhou 215004

RNA interfering therapy has emerged as a promising therapeutic modality to treat *** specific and efficient delivery of RNA into a tumor is crucial for achieving effective cancer gene therapy but remains a huge ***,we report a novel furin-responsive small interfering RNA(siRNA)delivery vehicle with multiple functions for colorectal tumor treatment.A peptide-based siRNA delivery vehicle RVRR-P18-Gd,consisting of furin enzyme-specific peptide substrate Arg-Val-Arg-Arg(RVRR)with positive charge for siRNA binding,a Gd(III)chelated 1,4,7,10-tetraazacyclododecane-N,N′,N″,N‴-tetraacetic acid(DOTA)(DOTA-Gd)for magnetic resonance imaging,and purpurin 18 as photosensitizer for photodynamic therapy(PDT),was rationally designed and *** advantage of the cationic amphiphilic feature,RVRR-P18-Gd molecules spontaneously self-assembled with negatively charged Hif-1αsiRNA into stable nanoparticles via attractive electrostatic interaction,which effectively prevented siRNA degradation by nucleases,prolonged the circulation half-life,and enhanced tumor ***,the specific release of Hif-1αsiRNA mediated by endogenous furin significantly downregulated Hif-1αexpression in colorectal cancer cells,resulting in enhanced therapeutic susceptibility,and with the PDT effect,effectively suppressed HCT116 tumor growth in living *** work highlights a powerful and universal approach to precisely deliver siRNA to targeted tumors for efficient synergistic therapy.

关键词： self-assembly RNA interfering enzymeresponsive delivery anti-hypoxia photodynamic therapy

Synthetic Aperture Positioning: A Review

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Journal of Beijing Institute of Technology 2024年第2期33卷 89-102页

作者： Guangcai Sun Wenlong Dong yuqi Wang Mengdao Xing National Key Laboratory of Radar Signal Processing Xidian UniversityXi’an 710071China School of Communication and Information Engineering Xi’an University of Science and TechnologyXi’an 710054China National Key Laboratory of Radar Signal Processing and the Academy of Advanced Interdisciplinary Research DepartmentXidian UniversityXi’an 710071China

Obtaining precise position of interested emitters passively has wide applications in both civilian and military *** from traditional parameter measurement and direct position determination(DPD)method,recently a new passive localization method based on synthetic aper-ture technique,named synthetic aperture positioning(SAP),has been *** method com-pensates for the nonlinear phase produced by relative motion between the moving platform and the emitter,achieving coherent summation of intercepted *** SAP can obtain high-resolution and high-precision localization results at a low signal-to-noise *** paper summarizes the research progress of SAP,including localization principles,spaceborne applications,and application scope ***,the possible future outlook of SAP is considered.

关键词： passive localization synthetic aperture positioning coherent processing

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天然白桦林经营调控技术及目标管理

东北林业大学学报 2009年第4期37卷 16-17,36页

作者：何玉琦吉林森工集团松江河林业有限公司吉林抚松134504

传统抚育技术间小留大不全面适用白桦林,提出分龄组、分林层、分树种、分径级经营,不同间伐强度标准的技术目标管理。在成熟林中有不成熟林木存在,在未成熟林中有成熟林木存在,用径级工艺成熟取替龄级工艺成熟,把森林利用着眼点从成、... 详细信息

传统抚育技术间小留大不全面适用白桦林,提出分龄组、分林层、分树种、分径级经营,不同间伐强度标准的技术目标管理。在成熟林中有不成熟林木存在,在未成熟林中有成熟林木存在,用径级工艺成熟取替龄级工艺成熟,把森林利用着眼点从成、过熟林两个龄组,拓广到全部龄组上来,发挥森林总体产出功能。林分立木株数分布序列,在平均直径以下,中、小径木占70%,蓄积占30%;平均直径以上,大径木占30%,其蓄积占70%;在中龄林以上,间伐15%～20%大径木株数,其蓄积占40%～50%。

关键词：天然林白桦林经营技术目标管理

Cultivating the uncultured:Harnessing the“sandwich agar plate”approach to isolate heme-dependent bacteria from marine sediment

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mLife 2024年第1期3卷 143-155页

作者： Jing Zhang Qi-Yun Liang Da-Shuai Mu Fengbai Lian Ya Gong Mengqi Ye Guan-Jun Chen yuqi Ye Zong-Jun Du State Key Laboratory of Microbial Techlogy Insttute of Micrbial TchnoogyShandong UniversityQingdaoChina Marine College Shandong UniverstyWeihaiChina Shandong University-Weihai Research Institute of Industrial Technology WeihaiChina

In the classical microbial isolation technique,the isolation process inevitably destroys all microbial interactions and thus makes it difficult to culture the many microorganisms that rely on these interactions for *** this study,we designed a simple coculture technique named the“sandwich agar plate method,”which maintains microbial interactions throughout the isolation and pure culture *** total yield of uncultured species in sandwich agar plates based on eight helper strains was almost 10-fold that of the control *** uncultured species displayed commensal *** study found that heme was the growth-promoting factor of some marine commensal *** genomic analysis revealed that heme auxotrophies were common in various biotopes and prevalent in many uncultured microbial ***,our study supported that the survival strategies of heme auxotrophy in different habitats varied *** findings highlight that cocultivation based on the“sandwich agar plate method”could be developed and used to isolate more uncultured bacteria.

关键词： cultivation growth factors heme sandwich agar plate uncultured bacteria

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基于主动激励的掘进机回转台振动抑制研究

煤炭科学技术 2024年第6期52卷 185-196页

作者：谢苗王贺李玉岐刘治翔辽宁工程技术大学机械工程学院辽宁阜新123000

悬臂式掘进机截割过程由于煤岩形状、硬度分布的随机性,当截割到硬岩时截割头会产生无规则的剧烈振动,瞬时高强度的冲击对掘进机关键受力部件回转台影响最大,其动态可靠性和寿命影响着截割效率和截割稳定性,为减弱截割过程回转台的振动... 详细信息

悬臂式掘进机截割过程由于煤岩形状、硬度分布的随机性,当截割到硬岩时截割头会产生无规则的剧烈振动,瞬时高强度的冲击对掘进机关键受力部件回转台影响最大,其动态可靠性和寿命影响着截割效率和截割稳定性,为减弱截割过程回转台的振动,首先,基于截割现场回转台易失效损坏现象,建立截割过程回转台力学模型,推导回转台力学方程,研究回转台受力随截割参数变化规律;通过搭建截割试验台,测试截割过程回转台振动响应,结合有限元进行回转台振动模态分析,求解回转台前6阶固有频率及振型,分析回转台剧烈振动的原因。其次,基于工况路径分析理论,建立截割过程回转台工况传递路径分析模型,模拟回转台合成振动,分析各激励点对回转台振动贡献量及贡献程度,准确找到回转台主要激振源。最后,通过施加外部主动激励的方式,分析不同激励频率加载下回转台振动情况,探寻能够降低截割过程回转台振动的激励频段。试验结果表明:外部激振频率处于20~60 Hz,回转台振动幅值降低明显,此频段激励频率对回转台振动控制效果良好,有益于提高回转台寿命,且激振频率为40 Hz时回转台振动最小,回转台振动抑制效果最佳。研究结果有益于丰富回转台振动相关研究理论,实现在不改变机械结构基础上,降低回转台受力与结构变形,可为掘进机回转台的振动问题提供理论参考。

关键词：掘进机回转台空间力学模型工况传递路径激振源主动激励振动控制

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Multifunctional interfacial molecular bridge enabled by an aggregation-induced emission strategy for enhancing efficiency and UV stability of perovskite solar cells

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Journal of Energy Chemistry 2024年第8期95卷 588-595,I0013页

作者： Shuhang Bian yuqi Wang Fancong Zeng Zhongqi Liu Bin Liu Yanjie Wu Long Shao Yongzhi Shao Huan Zhang Shuainan Liu Jin Liang Xue Bai Lin Xu Donglei Zhou Biao Dong Hongwei Song State Key Laboratory on Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012JilinChina College of Science Shanghai UniversityShanghai 200444China

The interface defects between the electron transport layer(ETL)and the perovskite layer,as well as the low ultraviolet(UV)light utilization rate of the perovskite absorption layer,pose significant challenges for the commercialization of perovskite solar cells(PSCs).To address this issue,this paper proposes an innovative multifunctional interface modulation strategy by introducing aggregation-induced emission(AIE)molecule 5-[4-[1,2,2-tri[4-(3,5-dicarboxyphenyl)phenyl]ethylene]phenyl]benzene-1,3-dicarboxylic acid(H_(8)ETTB)at the SnO_(2)ETL/perovskite ***,the interaction of H_(8)ETTB with the SnO_(2)surface,facilitated by its carboxyl groups,is effective in passivating surface defects caused by noncoord inated Sn and O *** interaction enhances the conductivity of the SnO_(2)film and adjusts energy levels,leading to enhanced charge carrier ***,H_(8)ETTB can passivate noncoord inated Pb^(2+)ions at the perovskite interface,promoting perovskite crystallization and reducing the interface energy barrier,resulting in a perovskite film with low defects and high crystalline *** importantly,the H_(8)ETTB molecule,can convert UV light into light absorbable by the perovskite,thereby reducing damage caused by UV light and improving the device's utilization of ***,the champion PSC based on SnO_(2)-H_(8)ETTB achieves an impressing efficiency of 23.32%and significantly improved photostability compared with the control device after continuous exposure to intense UV *** addition,the Cs_(0.05)(FA_(0.95)MA_(0.05))_(0.95)Pb(I_(0.95)Br_(0.05))_(3)based device can achieve maximum efficiency of 24.01%,demonstrating the effectiveness and universality of this ***,this innovative interface bridging strategy effectively tackles interface defects and low UV light utilization in PSCs,presenting a promising approach for achieving highly efficient and stable PSCs.

关键词： Perovskite solar cells Aggregation-induced emission Defect passivation Efficiency UV stability

新型测绘视角下的山地城市规划实施场景预警模拟技术探索

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测绘通报 2022年第4期 11-15页

作者：贺瑜琦曾一笑陈光陈良超重庆市勘测院重庆401121 重庆市地理国情监测工程技术研究中心重庆401121

面向支撑自然资源部“两统一”职责履行和基础测绘“两支撑、一提升”根本定位,测绘行业更新、技术创新、产品革新体现出更加聚焦应用服务导向的特点。在新型测绘智能化转型的视角下,本文聚焦自然资源管理中国土空间规划实施与监督环节... 详细信息

面向支撑自然资源部“两统一”职责履行和基础测绘“两支撑、一提升”根本定位,测绘行业更新、技术创新、产品革新体现出更加聚焦应用服务导向的特点。在新型测绘智能化转型的视角下,本文聚焦自然资源管理中国土空间规划实施与监督环节,针对城市尺度规划实施场景预警指标的多样性和场景构建的复杂性等问题,探索了一套服务于山地城市规划实施场景预警模拟的技术框架,并在典型区域开展建(构)筑物水位动态淹没预警模拟应用示范,支撑规划编制与动态维护的后续环节,助力国土空间规划形成闭环管理。

关键词：新型测绘规划实施预警模拟地理场景山地城市