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重金属铊对水稻叶和种子元素积累的影响

种子 2008年第1期27卷 43-46页

作者：姚焱张平汪珍春陈永亨广州大学生命科学学院广州510006 广州大学环境科学与工程学院广州510006

研究重金属铊在水稻叶和种子中累积分布以及铊对其它元素吸收积累的影响。结果表明,水稻中铊含量随土壤铊浓度升高而增加,叶比种子更易累积铊;铊会影响水稻对其它元素的吸收,并且在叶与种子中的吸收规律存在差异:随铊浓度升高,水稻叶中... 详细信息

研究重金属铊在水稻叶和种子中累积分布以及铊对其它元素吸收积累的影响。结果表明,水稻中铊含量随土壤铊浓度升高而增加,叶比种子更易累积铊;铊会影响水稻对其它元素的吸收,并且在叶与种子中的吸收规律存在差异:随铊浓度升高,水稻叶中必需元素Fe、Mn及非必需元素Al、Ni、Ba吸收量逐渐减少;水稻籽粒中,必需元素Mn、Cu及非必需元素Ni、Ba吸收量逐渐减少,但必需元素B、Mo及非必需元素Ag、Pb、Co等吸收量逐渐增加。

关键词：铊水稻种子叶元素积累

带蒂脂肪片加几丁糖预防腰椎间盘突出术后硬膜外瘢痕形成

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中国骨与关节损伤杂志 2012年第5期27卷 415-417页

作者：王春祯李登禄山东省德州市中医院骨科 253013

目的探讨带蒂脂肪片与几丁糖预防腰椎间盘突出术后硬膜外瘢痕形成的临床效果。方法对自2001年1月。2006年1月收治的符合纳入标准120例腰椎间盘突出症进行回顾性研究。其中随访完整者带蒂脂肪片与几丁糖组34例（A组），带蒂脂肪片组35例... 详细信息

目的探讨带蒂脂肪片与几丁糖预防腰椎间盘突出术后硬膜外瘢痕形成的临床效果。方法对自2001年1月。2006年1月收治的符合纳入标准120例腰椎间盘突出症进行回顾性研究。其中随访完整者带蒂脂肪片与几丁糖组34例（A组），带蒂脂肪片组35例（B组），几丁糖组33例（C组）。结果102例获随访5～8年，平均6年6个月。术后8周各治疗组间差异无统计学意义（χ^2=0．046，P=0．87）。5年以上随访结果：3组疗效有统计学意义（χ^2=7．23，P=0．03），其中，A组与B组间差异无统计学意义（χ^2=0．289，P=0．628）；A组与C组间差异有统计学意义（χ^2=6．017，P=0．016），B组与C组间差异有统计学意义（χ^2=3．875，P=0．047）。结论单独使用几丁糖能够获得较好的近期疗效，长期随访结果显示：带蒂脂肪片能有效减少腰椎间盘突出术后硬膜及神经根周围的纤维化与粘连，带蒂脂肪片加几丁糖两者具有协同作用，较单一材料应用效果更肯定。

关键词：椎板切除术椎间盘切除术瘢痕粘连

Chiral phosphoramidite ligand-modulated palladium auto-tandem catalysis for asymmetric dehydrogenative dienylation of imines with α-alkenes

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Science China Chemistry 2025年

作者： Zhong-Sheng Nong Hao-Fan Qian Ying-chun Chen Pu-Sheng wang Liu-Zhu Gong Hefei National Research Center for Physical Sciences at the Microscale and Department of Chemistry University of Science and Technology of China Key Laboratory of Drug Targeting and Drug Delivery System (Sichuan University) Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of Pharmacy Sichuan University School of Materials and Chemistry Southwest University of Science and Technology

The development of efficient processes allowing rapid access to complex chiral molecules from easily available alkenes is a long-term pursuit in the synthetic chemistry community. Transition metal-catalyzed asymmetric functionalization of allylic C–H bond represents a unique alternative toward this goal. However, enantioselective dehydrogenative transformation of olefins to value-added optically enriched molecules remains yet to be discovered. Here, we report a highly enantioselective dehydrogenative dienylation of imines with unactivated α-alkenes driven by the synergistic action of palladium complex and carboxylic acid. Chiral phosphoramidite ligands turned out to be superior in modulating the performance of palladium autotandem catalysis and allowed a broad range of α-alkenes and imines to be transformed into chiral dienylamines. Mechanistic studies suggest that the dienes could be in situ generated from α-alkenes through a palladium(0)-mediated dehydrogenative process in the presence of excess benzoquinone oxidants, and then participated in the Pd-chiral phosphoramidite-catalyzed intermolecular vinylogous-type addition to the imines activated by the carboxylic acid co-catalyst. Notably, the second β-H elimination occurring in the dienylation event might be the turnover-limiting step.

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Wafer‑Scale Ag_(2)S‑Based Memristive Crossbar Arrays with Ultra‑Low Switching‑Energies Reaching Biological Synapses

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Nano-Micro Letters 2025年第3期17卷 328-339页

作者： Yuan Zhu Tomas Nyberg Leif Nyholm Daniel Primetzhofer Xun Shi zhen Zhang Division of Solid‑State Electronics Department of Electrical EngineeringUppsala University75121 UppsalaSweden Department of Chemistry Uppsala UniversityUppsalaSweden Department of Physics and Astronomy Uppsala UniversityUppsalaSweden State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050People’s Republic of China

Memristive crossbar arrays(MCAs)offer parallel data storage and processing for energy-efficient neuromorphic ***,most wafer-scale MCAs that are compatible with complementary metal-oxide-semiconductor(CMOS)technology still suffer from substantially larger energy consumption than biological synapses,due to the slow kinetics of forming conductive paths inside the memristive *** we report wafer-scale Ag_(2)S-based MCAs realized using CMOS-compatible processes at temperatures below 160℃.Ag_(2)S electrolytes supply highly mobile Ag+ions,and provide the Ag/Ag_(2)S interface with low silver nucleation barrier to form silver filaments at low energy *** further enhancing Ag+migration in Ag_(2)S electrolytes via microstructure modulation,the integrated memristors exhibit a record low threshold of approximately−0.1 V,and demonstrate ultra-low switching-energies reaching femtojoule values as observed in biological *** low-temperature process also enables MCA integration on polyimide substrates for applications in flexible ***,the intrinsic nonidealities of the memristive units for deep learning can be compensated by employing an advanced training *** impressive accuracy of 92.6%in image recognition simulations is demonstrated with the MCAs after the *** demonstrated MCAs provide a promising device option for neuromorphic computing with ultra-high energy-efficiency.

关键词： Wafer-scale Ag_(2)S films Reactive sputter Silver nucleation Ag^(+)migration Energy-efficient neuromorphic computing

Constructing 2D bismuth-based heterostructure for highly efficient photocatalytic CO2 reduction

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Tungsten 2025年第1期7卷 71-79页

作者： Ruo-Hang Xu Hao-Yu Jiang Dan-Dan Cui Kun-Rong Du Hong-Run Zhang Sheng-Jie Xu Ya-Qi Li Zhi-zhen Ren Liang wang Wei-Chang Hao Yi Du School of Physics and BUAA-UOW Joint Research Centre Beihang University Shenzhen Institute of Beihang University Centre for Catalysis and Clean Energy School of Environment and Science Griffith University

Reforming carbon dioxide（CO2） into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply *** recombination of photocarriers remains a major obstacle,however,to enhancing solar energy conversion efficiency in the photocatalytic reaction *** two-dimensional materials,constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous ***,we present a facile strategy for preparing Bi4NbO8Br/Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situ *** unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral ***,the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties,along with a CO yield rate of approximately 35 μmol·g-1·h-1under full light *** work offers novel insights into the synthesis of unique hetero structures intended to enhance the efficiency of photocatalytic CO2reduction.

关键词： Bi4NbO8Br/Bi2WO6 CO2 reduction Heterostructures Photocatalysts

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人工黄土坡面重力侵蚀数值模拟

中国农村水利水电 2020年第8期 40-45页

作者：金鑫刘喆王春振宋颖赵华荣王迪李霞桂林理工大学广西环境污染控制理论与技术重点实验室广西桂林541004 桂林理工大学岩溶地区水污染控制与用水安全保障协同创新中心广西桂林541004

为研究人工黄土坡面重力侵蚀现象,通过应用有限差分软件FLAC3D对复杂侵蚀地形模型进行二次开发,分析坡面重力侵蚀过程,并对坡面位移场、应力场和塑性屈服区进行了数值模拟。结果表明:通过软件建立的三维模型能真实地还原侵蚀坡面地形地... 详细信息

为研究人工黄土坡面重力侵蚀现象,通过应用有限差分软件FLAC3D对复杂侵蚀地形模型进行二次开发,分析坡面重力侵蚀过程,并对坡面位移场、应力场和塑性屈服区进行了数值模拟。结果表明:通过软件建立的三维模型能真实地还原侵蚀坡面地形地貌,仿真效果良好;通过监测点位移规律,将侵蚀分为3个阶段,坡面下部侵蚀发育阶段要早于坡面中上部侵蚀发育完成;坡面位移以向下侵蚀滑落为主,且随坡度增加导致应力集中,在一定程度上坡度的增加,加剧了重力侵蚀的发生;通过对三次连续性降雨坡面进行受力分析,发现本场次侵蚀地形基本符合上一场模型平衡状态时的塑性区分布情况,说明FLAC3D在一定程度上能够对侵蚀地形发育起到预测的作用。

关键词：人工黄土坡面数值模拟重力侵蚀

Pathogenesis, diagnosis, and treatment of epilepsy: electromagnetic stimulation-mediated neuromodulation therapy and new technologies

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Neural Regeneration Research 2025年第4期20卷 917-935页

作者： Dian Jiao Lai Xu zhen Gu Hua Yan Dingding Shen Xiaosong Gu Academy of Medical Engineering and Translational Medicine Tianjin UniversityTianjinChina Key Laboratory of Advanced Drug Delivery Systems of Zhejiang Province College of Pharmaceutical SciencesZhejiang UniversityHangzhouZhejiang ProvinceChina Affiliated Hospital of Nantong University NantongJiangsu ProvinceChina

Epilepsy is a severe,relapsing,and multifactorial neurological *** regarding the accurate diagnosis,prognosis,and in-depth pathogenesis are crucial for the precise and effective treatment of *** pathogenesis of epilepsy is complex and involves alterations in variables such as gene expression,protein expression,ion channel activity,energy metabolites,and gut microbiota *** results are lacking for conventional treatments for *** resection of lesions,drug therapy,and non-drug interventions are mainly used in clinical practice to treat pain associated with ***-pharmacological treatments,such as a ketogenic diet,gene therapy for nerve regeneration,and neural regulation,are currently areas of research *** review provides a comprehensive overview of the pathogenesis,diagnostic methods,and treatments of *** also elaborates on the theoretical basis,treatment modes,and effects of invasive nerve stimulation in neurotherapy,including percutaneous vagus nerve stimulation,deep brain electrical stimulation,repetitive nerve electrical stimulation,in addition to non-invasive transcranial magnetic stimulation and transcranial direct current *** studies have shown that electromagnetic stimulation-mediated neuromodulation therapy can markedly improve neurological function and reduce the frequency of epileptic ***,many new technologies for the diagnosis and treatment of epilepsy are being ***,current research is mainly focused on analyzing patients’clinical manifestations and exploring relevant diagnostic and treatment methods to study the pathogenesis at a molecular level,which has led to a lack of consensus regarding the mechanisms related to the disease.

关键词： diagnosis drug treatment electroencephalography epilepsy monitoring epilepsy nerve regeneration neurostimulation non-drug interventions pathogenesis prediction

偏最小二乘模型在黄土坡面土壤侵蚀中的应用研究

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中国农村水利水电 2020年第12期 117-121页

作者：金鑫李霞宋颖王春振赵华荣桂林理工大学广西环境污染控制理论与技术重点实验室广西桂林541004 桂林理工大学岩溶地区水污染控制与用水安全保障协同创新中心广西桂林541004

选取不同坡度(5°、10°、15°、20°)和不同雨强(50、60、70、80 mm/h)的16场降雨,利用偏最小二乘模型研究了坡度、雨强、降雨历时、土壤初始含水率、剪切力5个因素对黄土坡面土壤侵蚀过程的影响程度。结果表明:①变量对数化处理后,偏... 详细信息

选取不同坡度(5°、10°、15°、20°)和不同雨强(50、60、70、80 mm/h)的16场降雨,利用偏最小二乘模型研究了坡度、雨强、降雨历时、土壤初始含水率、剪切力5个因素对黄土坡面土壤侵蚀过程的影响程度。结果表明:①变量对数化处理后,偏最小二乘模型模拟精度和预测优度均达到0.8以上,径流率和产沙率相关系数为0.844;②VIP值显示,时间X3、坡度X1是驱动降雨初期径流率Y1和产沙率Y2变化的重要因素,其中时间X3是最重要的影响因素;雨强对径流率和产沙率影响均较大,标准回归系数分别为0.408、0.341,初始含水率、剪切力的标准回归系数最大仅为0.145,表明二者对径流率和产沙率的影响都比较有限;③精度分析结果表明,模型模拟和预测精度都较高,与产沙率相比,径流率的预测精度更高,平均相对误差绝对值为18.813%,模拟预测的效果更好。

关键词：坡度降雨强度土壤侵蚀偏最小二乘模型

低温预处理对水稻花药培养中花药壁褐变的结构影响

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热带亚热带植物学报 2006年第4期14卷 307-311页

作者：姚焱刘向东汪珍春张桂权张平广州大学生命科学学院广州510006 华南农业大学植物分子育种研究中心广州510642

药壁褐变是影响花药离体培养效率的因素。研究了粳稻品种台中6(5OryzasatvaL.)花药培养前低温预处理对药壁褐变的影响,观察了花药褐变前后药壁各层的变化及褐变对小孢子发育的作用。结果表明:药壁褐变主要发生在表皮与药室内壁。10℃低... 详细信息

药壁褐变是影响花药离体培养效率的因素。研究了粳稻品种台中6(5OryzasatvaL.)花药培养前低温预处理对药壁褐变的影响,观察了花药褐变前后药壁各层的变化及褐变对小孢子发育的作用。结果表明:药壁褐变主要发生在表皮与药室内壁。10℃低温预处理在花药培养前期可有效延缓表皮与药室内壁膜结构的降解速度,减缓褐变发生;花药经低温处理后,药壁中层细胞膨大,绒毡层降解速度减缓,有利于花粉脱分化。药壁褐变会影响药腔内小孢子的活力和继续发育,但不是制约花粉愈伤组织形成的关键因素。

关键词：水稻花药培养低温处理花药壁褐变解剖学