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Geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review
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作者 Shi-min Zhen Da-zhao wang +2 位作者 Zhong-jian Zha Hai-jun Bai jiang wang 《China Geology》 CAS CSCD 2024年第3期533-550,共18页
The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization origi... The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of Au.This paper presents a new understanding for Dongping ore system,based on the previous studies.The mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the Yanshanian.Isotope compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou complex.Ore-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2 and decreased in Stage II-3.These systematic changes are closely related to the processes of mineral precipitation and fluid evolution.Sulfide precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur fugacity.Condensation of gas phase containing high concentration of H_2Te leads to precipitation of Te-Au-Ag minerals and native tellurium.Based on these hypotheses,this paper present a polyphase metallogenic model as follow.During the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early ores.During the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit. 展开更多
关键词 Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton Mineral exploration engineering
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人工智能背景下医养机构室内空间生成系统构建
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作者 吕阳 汪江 王家伟 《工程设计与施工》 2024年第7期38-40,共3页
随着人工智能与大数据技术的广泛应用,医养结合养老服务模式有望实现服务的多样化与个性化,不仅能满足老年群体多元化的需求,还可提升医养服务的价值与社会效益。以其便捷化、个性化、专业化、智能化的特点,以及资源共享互济、优化配置... 随着人工智能与大数据技术的广泛应用,医养结合养老服务模式有望实现服务的多样化与个性化,不仅能满足老年群体多元化的需求,还可提升医养服务的价值与社会效益。以其便捷化、个性化、专业化、智能化的特点,以及资源共享互济、优化配置的优势,正成为中国医养行业未来发展的新趋势。由于人口老龄化的趋势日益明显,医养机构的需求也在不断增加。从人工智能的角度来进行养老构成要素,以提高医疗服务的效率和质量为老年人提供更加完善、全面的关怀。 展开更多
关键词 医养机构 人工智能 室内空间 系统构建
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Hydrophobic CHA-ZIFs with a junctional trap between cha and d6r cages for adsorption of 2,3-butanediol in aqueous solution
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作者 Lifang Ge Meizhen Gao +3 位作者 Xiaosheng Zhang jiang wang Qi Shi Jinxiang Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期90-100,共11页
The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic ... The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diol-water hydrogen-bonding interactions. Herein, we screened hydrophobic zeolitic imidazolate frameworks(ZIFs) with chabazite(CHA) topology for separation of 2,3-butanediol(2,3-BDO) and 1,3-propanediol(1,3-PDO), which had junctional and hydrophobic traps matching the two end methyl groups of the 2,3-BDO molecule. Based on CHA-ZIFs with the same small-sized ligand 2-methylimidazole(mIm) and different large-sized ligand benzimidazole derivatives(RbIm),CHA-ZIFs with larger surface areas were obtained by the addition of excess small-sized ligand mIm in the synthesis process. We showed that all of the hydrophobic CHA-ZIFs preferentially adsorbed 2,3-BDO over 1,3-PDO by static batch adsorption and dynamic column adsorption experiments. But ZIF-301 and ZIF-300 with halogen groups exhibited better adsorptive separation performance for 2,3-BDO/1,3-PDO than ZIF-302 with methyl groups. For a typical ZIF-301, its adsorption capacity for 2,3-BDO was 116.4 mg·g^(-1)and selectivity for 2,3-BDO/1,3-PDO was 3.8 in dynamic column adsorption of the binary-component system(2,3-BDO/1,3-PDO: 50 g·L^(-1)/50 g·L^(-1)). Computational simulations revealed that 2,3-BDO preferentially adsorbed in a trap at the junction between the cha and d6r cages of CHA-ZIFs,meaning the strong host-guest interactions. Therefore, the hydrophobic CHA-ZIFs with a junctional trap were promising candidate materials for adsorbing 2,3-BDO, which also provided a new perspective for separating diols in dilute aqueous solutions. 展开更多
关键词 Adsorption Separation Aqueous solution Zeolitic imidazolate frameworks Junctional and hydrophobic trap DIOLS
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A Layered Energy-Efficient Multi-Node Scheduling Mechanism for Large-Scale WSN
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作者 Xue Zhao Shaojun Tao +2 位作者 Hongying Tang jiang wang Baoqing Li 《Computers, Materials & Continua》 SCIE EI 2024年第4期1335-1351,共17页
In recent years, target tracking has been considered one of the most important applications of wireless sensornetwork (WSN). Optimizing target tracking performance and prolonging network lifetime are two equally criti... In recent years, target tracking has been considered one of the most important applications of wireless sensornetwork (WSN). Optimizing target tracking performance and prolonging network lifetime are two equally criticalobjectives in this scenario. The existing mechanisms still have weaknesses in balancing the two demands. Theproposed heuristic multi-node collaborative scheduling mechanism (HMNCS) comprises cluster head (CH)election, pre-selection, and task set selectionmechanisms, where the latter two kinds of selections forma two-layerselection mechanism. The CH election innovatively introduces the movement trend of the target and establishesa scoring mechanism to determine the optimal CH, which can delay the CH rotation and thus reduce energyconsumption. The pre-selection mechanism adaptively filters out suitable nodes as the candidate task set to applyfor tracking tasks, which can reduce the application consumption and the overhead of the following task setselection. Finally, the task node selection is mathematically transformed into an optimization problem and thegenetic algorithm is adopted to form a final task set in the task set selection mechanism. Simulation results showthat HMNCS outperforms other compared mechanisms in the tracking accuracy and the network lifetime. 展开更多
关键词 Node scheduling pre-selection target tracking WSN
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某选矿厂树脂吸附金试验研究
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作者 于淙权 李春晖 +2 位作者 蒋旺 董广强 徐广平 《世界有色金属》 2024年第13期196-198,共3页
某选矿厂采用全泥氰化-树脂提金工艺,对所用的树脂吸附金影响因素进行了试验分析,重点研究了温度、硫氰酸盐对树脂吸附的影响,研究表明流程中存在的硫氰酸盐可使载金树脂解吸,降低载金树脂的品位;温度对树脂吸附金有很大影响,温度越高,... 某选矿厂采用全泥氰化-树脂提金工艺,对所用的树脂吸附金影响因素进行了试验分析,重点研究了温度、硫氰酸盐对树脂吸附的影响,研究表明流程中存在的硫氰酸盐可使载金树脂解吸,降低载金树脂的品位;温度对树脂吸附金有很大影响,温度越高,载金树脂品位越低,当温度达到30℃时载金树脂同时存在吸附与解吸现象;针对以上问题车间采取了针对性的措施,通过散热塔降低贵液的温度,采用活性炭对电解废液进行处理,降低硫氰酸盐的含量,减少对流程的影响,稳定现场的生产指标。 展开更多
关键词 树脂吸附 影响因素 试验研究
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基于改进P-f下垂方程的构网型逆变器主动孤岛检测方法
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作者 魏友金 蒋旺 +2 位作者 黄顺权 江晨 陈凯龙 《电工技术》 2024年第2期9-12,共4页
目前大多数孤岛检测算法是针对跟网型逆变器设计的,对基于下垂控制的构网型逆变器并不适用。被动孤岛检测方法在基于下垂控制的系统中,由于下垂系数设计偏小且系统本身存在负反馈特性,因此只有在负荷功率与逆变器输出功率严重不匹配的... 目前大多数孤岛检测算法是针对跟网型逆变器设计的,对基于下垂控制的构网型逆变器并不适用。被动孤岛检测方法在基于下垂控制的系统中,由于下垂系数设计偏小且系统本身存在负反馈特性,因此只有在负荷功率与逆变器输出功率严重不匹配的工况下才能检测到孤岛,检测盲区大。常规主动孤岛检测方法需要加入扰动来实现孤岛检测,对系统的电能质量影响较大。为此,提出一种基于改进P-f下垂方程的主动孤岛检测方法。在并网稳定之后加入电压偏差增量,一旦大电网端瞬间失电,就通过新的下垂方程计算此刻公共耦合点的频率,由于该量瞬间发生很大的波动且很快超过限定值,因此孤岛检测可以迅速完成,并且对系统的电能质量影响较小。最后在MATLAB/Simulink中进行不同工况的仿真验证,并且基于TMS320F28379D与Speedgoat实时仿真目标机进行实物验证。 展开更多
关键词 微电网 构网型逆变器 主动孤岛检测 下垂控制 电压偏差量
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施工场地无人机精细化三维模型构建及土方测量 被引量:11
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作者 余加勇 尹东 +3 位作者 刘宝麟 蒋望 杨宇驰 高文宇 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2023年第1期181-188,共8页
利用无人机倾斜摄影测量技术,获取工程施工场地多视图影像序列,利用基于运动恢复结构算法(Structure from Motion,SfM)和多视图立体匹配算法(Multi View Stereo,MVS)的多视影像密集匹配形成超高密度点云,采用布料模拟滤波(Cloth Simulat... 利用无人机倾斜摄影测量技术,获取工程施工场地多视图影像序列,利用基于运动恢复结构算法(Structure from Motion,SfM)和多视图立体匹配算法(Multi View Stereo,MVS)的多视影像密集匹配形成超高密度点云,采用布料模拟滤波(Cloth Simulation Filter,CSF)算法剔除植被及废弃建筑物点云,获取真实地面点云,基于基底设计模型计算出两期点云之间土方量,实现复杂土方工程智能化测量.采用上述无人机方法,对长沙岳麓山脚两块建设用地进行土方快速测量及精度评估,得到5.3846亿点/公顷的点云密度,土方计算结果相对于RTKGNSS测量结果误差为2.8%,满足土方测量误差小于5%的要求,具有较好的应用前景及工程实用价值. 展开更多
关键词 无人机 土方测量 倾斜摄影 布料模拟滤波
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分布式光伏无功电压主动支撑控制方法 被引量:4
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作者 郑许林 袁源 +3 位作者 柏晶晶 姜望 刘祎文 王亚祥 《可再生能源》 CAS CSCD 北大核心 2023年第12期1685-1690,共6页
新能源的波动性及不确定性给电网稳定运行带来了极大挑战,尤其是大规模分布式光伏接入配电网,潮流波动穿透式影响主网、配网电压,直接影响了电网的供电电压水平。为了解决电压质量问题,文章分析了配电网中无功功率与电压的关系,提出了... 新能源的波动性及不确定性给电网稳定运行带来了极大挑战,尤其是大规模分布式光伏接入配电网,潮流波动穿透式影响主网、配网电压,直接影响了电网的供电电压水平。为了解决电压质量问题,文章分析了配电网中无功功率与电压的关系,提出了基于母线电压下垂的光伏并网逆变器参与无功电压主动支撑方法。最后通过实验验证了所提方法的可行性和有效性。 展开更多
关键词 分布式光伏 逆变器 无功补偿 母线电压 下垂控制
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浮选法在赤霞珠葡萄果粒成熟度分级中的应用
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作者 朱雯莎 刘国安 +4 位作者 李茹一 蒋旺 李悦 张军翔 薛婷婷 《食品与发酵工业》 CAS CSCD 北大核心 2023年第12期100-105,共6页
在收获时,葡萄果实的异质性对葡萄成熟特性、葡萄酒组成和感官质量有重要影响。该研究针对葡萄异质性对赤霞珠果粒成熟度的影响,以及对浮选法所用溶液类型和使用方法步骤的探索,使用独立的浆果密度作为分类方法研究果实异质性对葡萄成... 在收获时,葡萄果实的异质性对葡萄成熟特性、葡萄酒组成和感官质量有重要影响。该研究针对葡萄异质性对赤霞珠果粒成熟度的影响,以及对浮选法所用溶液类型和使用方法步骤的探索,使用独立的浆果密度作为分类方法研究果实异质性对葡萄成熟特性的影响,如葡萄的大小、质量、含糖量、含酸量、酚类物质含量及葡萄酒的酒精度。根据赤霞珠浆果在不同蔗糖溶液中浮选的密度进行分类,选择了两个最具代表性质量浓度(315、320 g/L)的蔗糖溶液,将赤霞珠浆果分为3个密度等级,并分别使用不同等级的分选浆果进行酿酒。结果表明,不同水平的葡萄异质性对赤霞珠果实直径大小、成熟特性和葡萄酒酒精度有重要影响,该研究对行业葡萄分选方法的改革提供理论支持和技术指导。 展开更多
关键词 赤霞珠 葡萄成熟度 浆果密度 浆果大小 浮选法
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亚洲玉米螟CPT1蛋白的表达、纯化和与几丁质的结合能力
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作者 蒋望 包涵 +2 位作者 陈金利 刘田 杨青 《中国生物防治学报》 CSCD 北大核心 2023年第2期462-470,共9页
亚洲玉米螟Ostrinia furnacalis是为害我国主要农作物玉米的一种重要害虫。昆虫表皮在运动、抵御机械损伤及对抗外界环境压力等方面发挥关键性作用。Tweedle(CPT)家族表皮蛋白在形成昆虫表皮中发挥重要作用,研究CPT有助于开发新一代害... 亚洲玉米螟Ostrinia furnacalis是为害我国主要农作物玉米的一种重要害虫。昆虫表皮在运动、抵御机械损伤及对抗外界环境压力等方面发挥关键性作用。Tweedle(CPT)家族表皮蛋白在形成昆虫表皮中发挥重要作用,研究CPT有助于开发新一代害虫防治方法。本研究在大肠杆菌系统中以包涵体的形式重组表达了Of CPT1蛋白,使用金属螯合层析进行纯化,复性得到了Of CPT1蛋白,收率为50 mg/L。几丁质结合试验发现,Of CPT1对α-几丁质、β-几丁质、壳聚糖、胶体几丁质和几丁质纳米微晶均有一定的结合能力,其中与几丁质纳米微丝结合能力最强。圆二色光谱结果表明,Of CPT1蛋白与壳聚糖结合后二级结构从以α-螺旋占主导变为以β-折叠占主导。本研究利用原核表达系统获得了亚洲玉米螟重组CPT蛋白并表征了它的部分生物化学性质。 展开更多
关键词 表皮蛋白 Tweedle 几丁质结合 杀虫剂靶标
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Ultrasmall NiS_(2)Nanocrystals Embedded in Ordered Macroporous Graphenic Carbon Matrix for Efficiently Pseudocapacitive Sodium Storage 被引量:1
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作者 Zhaozhao Liu jiang wang +7 位作者 Ran Bi Pinyi Zhao Mengqian Wu Xinyu Liu Likun Yin Chengyang wang Mingming Chen Kemeng Ji 《Transactions of Tianjin University》 EI CAS 2023年第2期89-100,共12页
Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance betw... Sodium-ion hybrid capacitor(SIHC)is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities,natural abundance,and low cost.However,overcoming the imbalance between slow Na^(+)reaction kinetics of battery-type anodes and rapid ion adsorption/desorption of capacitive cathodes is a significant challenge.Here,we propose the high-rate-performance NiS_(2)@OMGC anode material composed of monodispersed NiS_(2) nanocrystals(8.8±1.7 nm in size)and N,S-co-doped graphenic carbon(GC).The NiS_(2)@OMGC material has a three-dimensionally ordered macroporous(3DOM)morphology,and numerous NiS_(2) nanocrystals are uniformly embedded in GC,forming a core-shell structure in the local area.Ultrafine NiS_(2) nanocrystals and their nano-microstructure demonstrate high pseudocapacitive Na-storage capability and thus excellent rate performance(355.7 mAh/g at 20.0 A/g).A SIHC device fabricated using NiS_(2)@OMGC and commercial activated carbon(AC)cathode exhibits ultrahigh energy densities(197.4 Wh/kg at 398.8 W/kg)and power densities(43.9 kW/kg at 41.3 Wh/kg),together with a long life span.This outcome exemplifies the rational architecture and composition design of this type of anode material.This strategy can be extended to the design and synthesis of a wide range of high-performance electrode materials for energy storage applications. 展开更多
关键词 Sodium-ion battery Sodium-ion hybrid capacitor Three-dimensionally ordered macroporous structure Graphenic carbon NiS_(2)nanocrystals
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未孕及已孕妇女血清维生素D_(2)和维生素D_(3)参考范围建立
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作者 江望 王华 《中国社区医师》 2023年第19期144-146,共3页
目的:统计未孕健康妇女及妊娠不同时期妇女血清脂溶性维生素D_(2)和维生素D_(3)水平,建立参考范围。方法:选取2022年4—9月于南京市妇幼保健院进行体检的健康妇女(n=135)和处于早期妊娠(n=160)、中期妊娠(n=119)、晚期妊娠(n=95)的健康... 目的:统计未孕健康妇女及妊娠不同时期妇女血清脂溶性维生素D_(2)和维生素D_(3)水平,建立参考范围。方法:选取2022年4—9月于南京市妇幼保健院进行体检的健康妇女(n=135)和处于早期妊娠(n=160)、中期妊娠(n=119)、晚期妊娠(n=95)的健康孕妇509例为观察对象,采用质谱技术进行血清维生素D_(2)和维生素D_(3)检测,计算各组95%置信区间作为参考范围。结果:健康未孕妇女血清维生素D_(2)和D_(3)参考范围分别为0.10~1.14 ng/mL、5.30~22.62 ng/mL。早期妊娠妇女血清维生素D_(2)和D_(3)参考范围为0.10~1.80 ng/mL、4.91~27.79 ng/mL。中期妊娠妇女血清维生素D_(2)和D_(3)参考范围为0.10~4.90 ng/mL、7.70~42.30 ng/mL。晚期妊娠妇女血清维生素D_(2)和D_(3)参考范围为0.10~12.26 ng/mL、7.64~47.78 ng/mL。结论:妊娠会影响血清维生素D_(2)和维生素D_(3)水平,要注意根据孕周建立合理的参考范围,以进行合理监测。 展开更多
关键词 妊娠 维生素D_(2) 维生素D_(3) 参考范围 质谱
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基于GB 50009新旧规范塔器风载荷计算的研究
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作者 许艳 孔惠 +1 位作者 蒋旺 高龙 《北京石油化工学院学报》 2023年第1期9-13,26,共6页
以某一塔器为例,对比GB 50009新旧规范中对风载荷计算的不同;并以塔器直径DN为3000 mm,基本风压q_(o)为550 N/m^(2),塔器自振周期T 1=0.013H,计算不同高度下塔器的顺风向风载荷,分析新旧规范下塔顶风载荷在不同地面粗糙度的情况,得到新... 以某一塔器为例,对比GB 50009新旧规范中对风载荷计算的不同;并以塔器直径DN为3000 mm,基本风压q_(o)为550 N/m^(2),塔器自振周期T 1=0.013H,计算不同高度下塔器的顺风向风载荷,分析新旧规范下塔顶风载荷在不同地面粗糙度的情况,得到新版规范风载荷有不同程度的增大,增大趋势为B类>A类>C类>D类,为设计人员在塔器风载荷计算时提供思路。 展开更多
关键词 风载荷 GB 50009 塔器
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Epigenetic modification associated with climate regulates betulin biosynthesis in birch
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作者 jiang wang Bowei Chen +13 位作者 Shahid Ali Tianxu Zhang Yu wang He Zhang Lishan wang Yonglan Zhang Linan Xie Tingbo jiang Jing Yin Heike W.Sederoff Gaurav Zinta Ronald R.Sederoff Yuhua Li Qingzhu Zhang 《Journal of Forestry Research》 SCIE CAS CSCD 2023年第1期21-35,共15页
The Betula genus contains pentacyclic triterpenoid betulin known for its environmental adaptation and medicinal properties.However,the mechanisms underlying betulin biosynthesis responding to climate change remain unc... The Betula genus contains pentacyclic triterpenoid betulin known for its environmental adaptation and medicinal properties.However,the mechanisms underlying betulin biosynthesis responding to climate change remain unclear.In this study,the role of epigenetic modification(DNA methylation) in betulin biosynthesis was examined and how climatic factors influence it.Whole-genome bisulfite sequencing was performed for greenhouse-grown Chinese white birch(Betula platyphylla Sukaczev) treated with DNA methylation inhibitor zebularine(ZEB) and a natural birch population in Northeast China.ZEB treatment significantly affected the CHH methylation level of transposable elements and betulin content in a hormesis dose-dependent manner.The methylation and expression of bHLH9,a key transcriptional factor controlling betulin biosynthesis,were also consistently affected by ZEB treatment as a hormetic dose-response.In the natural population,there was a positive correlation between promoter methylation of bHLH9 and summer precipitation,while winter temperature was negatively correlated.Thus climate-dependent methylation of bHLH9 regulates the expression of downstream genes involved in betulin biosynthesis.This study highlights the role of environmental signals to induce epigenetic changes that result in betulin production,possibly helping to develop resilient plants to combat ongoing climate change and enhance secondary metabolite production. 展开更多
关键词 EPIGENETICS DNA methylation BETULIN bHLH9 transcription factor HORMESIS Climate change Secondary metabolite
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利用微计算机断层扫描定量研究选择性激光熔化Ti6Al4V合金缺陷的几何特征及形成机理
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作者 安娜莹 帅三三 +3 位作者 陈超越 雷力明 王江 任忠鸣 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2023年第10期2986-3002,共17页
增材制造(AM)部件内部形成的缺陷对打印零件的力学性能具有不利影响。缺陷对零件性能的影响因其几何特征的不同而不同。利用X射线计算机层析成像(XCT)研究不同打印参数下36个块状Ti6Al4V样品的孔隙缺陷特征。根据样品中孔隙的几何特征,... 增材制造(AM)部件内部形成的缺陷对打印零件的力学性能具有不利影响。缺陷对零件性能的影响因其几何特征的不同而不同。利用X射线计算机层析成像(XCT)研究不同打印参数下36个块状Ti6Al4V样品的孔隙缺陷特征。根据样品中孔隙的几何特征,将孔隙缺陷分为4种类型:球形、椭圆形、长条形和不规则形。在所有工艺参数下,长条形状缺陷所占比例最大,并且随着扫描速度的提高,不规则形状缺陷所占比例逐渐增大。另外,分析单道和多道试样中缺陷逐渐积累规律。随着层的叠加,孔隙逐渐积累,而适当的搭接率可能会熔化道之间的气孔。表面粗糙度和熔池润湿对缺陷的形成有很大的影响。 展开更多
关键词 选择性激光熔化 X射线计算机断层扫描 气孔缺陷 3D几何形态 形成机制 TI6AL4V合金
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Melting and floating processes of inorganic materials in molten steel:Visualization physical simulation and mathematical modelling
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作者 Jin-hu Lai Sheng Yu +4 位作者 Yang-jian Xu Dan-qing jiang San-san Shuai jiang wang Zhong-ming Ren 《China Foundry》 SCIE CAS CSCD 2023年第2期89-98,共10页
It has been demonstrated that heat absorption method by using the inorganic material rod to cool the molten steel can significantly reduce the macrosegregation level of the large steel ingot.However,owing to the opaci... It has been demonstrated that heat absorption method by using the inorganic material rod to cool the molten steel can significantly reduce the macrosegregation level of the large steel ingot.However,owing to the opacity of the molten steel,the physical mechanism of the heat absorption method is not clear.In this work,a transparent hydraulic physical model with water and paraffin wax was built to simulate the melting and floating processes of inorganic materials in the molten steel.A mathematical simulation was also carried out to analyze the connection between the actual ingot and the physical model.Results show that it is feasible to simulate the molten steel and inorganic materials with water and paraffin wax.With the help of the physical model,the process of the melting of paraffin wax and its floating to the surface of water were clearly observed,during which the temperature of water at some characteristic positions in the mold was recorded.The visualization findings demonstrate that the melting and floating processes of paraffin wax can help to bring the heat from the center of the mold to the top surface more quickly,which reduces the superheat and significantly accelerates the cooling rate of water.The experimental results show that for the water with a certain superheat,the use of a larger mass of paraffin wax can accelerate the cooling of the water,but there is a risk of incomplete melting of the paraffin wax.A higher superheat of water will lead to a quicker melting rate for a given mass of paraffin wax,while a lower superheat leads to the incomplete melting of paraffin wax as well. 展开更多
关键词 water and paraffin wax heat absorption method physical simulation SUPERHEAT large steel ingot
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Quick and Accurate Counting of Rapeseed Seedling with Improved YOLOv5s and Deep-Sort Method
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作者 Chen Su Jie Hong +1 位作者 jiang wang Yang Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第9期2611-2632,共22页
The statistics of the number of rapeseed seedlings are very important for breeders and planters to conduct seed quality testing,field crop management and yield estimation.Calculating the number of seedlings is ineffic... The statistics of the number of rapeseed seedlings are very important for breeders and planters to conduct seed quality testing,field crop management and yield estimation.Calculating the number of seedlings is inefficient and cumbersome in the traditional method.In this study,a method was proposed for efficient detection and calculation of rapeseed seedling number based on improved you only look once version 5(YOLOv5)to identify objects and deep-sort to perform object tracking for rapeseed seedling video.Coordinated attention(CA)mechanism was added to the trunk of the improved YOLOv5s,which made the model more effective in identifying shaded,dense and small rapeseed seedlings.Also,the use of the GSConv module replaced the standard convolution at the neck,reduced model parameters and enabled it better able to be equipped for mobile devices.The accuracy and recall rate of using improved YOLOv5s on the test set by 1.9%and 3.7%compared to 96.2%and 93.7%of YOLOv5s,respectively.The experimental results showed that the average error of monitoring the number of seedlings by unmanned aerial vehicles(UAV)video of rapeseed seedlings based on improved YOLOv5s combined with depth-sort method was 4.3%.The presented approach can realize rapid statistics of the number of rapeseed seedlings in the field based on UAV remote sensing,provide a reference for variety selection and precise management of rapeseed. 展开更多
关键词 Rapeseed seedling UAV improved YOLOv5s attention mechanism real-time detection
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Risk Analysis Using Multi-Source Data for Distribution Networks Facing Extreme Natural Disasters
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作者 Jun Yang Nannan wang +1 位作者 jiang wang Yashuai Luo 《Energy Engineering》 EI 2023年第9期2079-2096,共18页
Distribution networks denote important public infrastructure necessary for people’s livelihoods.However,extreme natural disasters,such as earthquakes,typhoons,and mudslides,severely threaten the safe and stable opera... Distribution networks denote important public infrastructure necessary for people’s livelihoods.However,extreme natural disasters,such as earthquakes,typhoons,and mudslides,severely threaten the safe and stable operation of distribution networks and power supplies needed for daily life.Therefore,considering the requirements for distribution network disaster prevention and mitigation,there is an urgent need for in-depth research on risk assessment methods of distribution networks under extreme natural disaster conditions.This paper accessesmultisource data,presents the data quality improvement methods of distribution networks,and conducts data-driven active fault diagnosis and disaster damage analysis and evaluation using data-driven theory.Furthermore,the paper realizes real-time,accurate access to distribution network disaster information.The proposed approach performs an accurate and rapid assessment of cross-sectional risk through case study.The minimal average annual outage time can be reduced to 3 h/a in the ring network through case study.The approach proposed in this paper can provide technical support to the further improvement of the ability of distribution networks to cope with extreme natural disasters. 展开更多
关键词 Distribution network disaster damage analysis fault judgment multi-source data
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Recent progress in understanding mitokines as diagnostic and therapeutic targets in hepatocellular carcinoma
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作者 jiang wang Lan-Zhu Luo +4 位作者 Dao-Miao Liang Chao Guo Zhi-Hong Huang Xiao-Hong Jian Jie Wen 《World Journal of Clinical Cases》 SCIE 2023年第23期5416-5429,共14页
Hepatocellular carcinoma(HCC)is one of the most prevalent tumors worldwide and the leading contributor to cancer-related deaths.The progression and metastasis of HCC are closely associated with altered mitochondrial m... Hepatocellular carcinoma(HCC)is one of the most prevalent tumors worldwide and the leading contributor to cancer-related deaths.The progression and metastasis of HCC are closely associated with altered mitochondrial metabolism,including mitochondrial stress response.Mitokines,soluble proteins produced and secreted in response to mitochondrial stress,play an essential immunomodulatory role.Immunotherapy has emerged as a crucial treatment option for HCC.However,a positive response to therapy is typically dependent on the interaction of tumor cells with immune regulation within the tumor microenvironment.Therefore,exploring the specific immunomodulatory mechanisms of mitokines in HCC is essential for improving the efficacy of immunotherapy.This study provides a comprehensive overview of the association between HCC and the immune microenvironment and highlights recent progress in understanding the involvement of mitochondrial function in preserving liver function.In addition,a systematic review of mitokines-mediated immunomodulation in HCC is presented.Finally,the potential diagnostic and therapeutic roles of mitokines in HCC are prospected and summarized.Recent progress in mitokine research represents a new prospect for mitochondrial therapy.Considering the potential of mitokines to regulate immune function,investigating them as a relevant mole cular target holds great promise for the diagnosis and treatment of HCC. 展开更多
关键词 Hepatocellular carcinoma MITOCHONDRIA Mitokine Immune escape AUTOPHAGY
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儿童血微量元素、铁蛋白及25羟维生素D的相关性研究
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作者 江望 王华 《中国卫生标准管理》 2023年第1期34-37,共4页
目的通过检测一定数量健康体检儿童血锌、钙、镁、铁、锰、铜、铅及铁蛋白、25羟维生素D含量,寻找这些项目之间存在的相关性,以便于更好地解释这些检验项目结果,更合理地选择相应检验项目。方法选取2021年6—9月101名健康体检儿童血标... 目的通过检测一定数量健康体检儿童血锌、钙、镁、铁、锰、铜、铅及铁蛋白、25羟维生素D含量,寻找这些项目之间存在的相关性,以便于更好地解释这些检验项目结果,更合理地选择相应检验项目。方法选取2021年6—9月101名健康体检儿童血标本用微分电位溶出法(differential potentiometric stripping analysis,DPSA)检测锌、钙、镁、铁、锰、铜、铅含量,用胶体金免疫层析法检测铁蛋白含量,用化学发光免疫分析法检测25羟维生素D含量。将检测得到的结果用SPSS25.0统计学软件进行统计并进行相关性分析。结果锌与铁呈正相关(r=0.297,P<0.05),钙与铜呈正相关,(r=0.210,P<0.05),锰与铜呈负相关(r=-0.227,P<0.05),镁与锰呈负相关(r=-0.218,P<0.05),铁蛋白与25羟维生素D呈正相关(r=0.212,P<0.05),铜与25羟维生素D呈正相关(r=0.209,P<0.05)。结论儿童血锌与铁、钙与铜、镁与锰、锰与铜、铜与25羟维生素D、铁蛋白与25羟维生素D之间存在一定相关性,在检测及解释这些项目结果时需要注意其相互影响,以免耽误疾病诊断治疗。 展开更多
关键词 儿童 铁蛋白 25羟维生素D 微分电位溶出法 胶体金免疫层析法 化学发光免疫分析法 微量元素
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