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Synergistic p-doping and interface passivation of P3HT by oxidized organic small molecules toward efficient and stable perovskite solar modules
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作者 Pin Lv Yuxi Zhang +9 位作者 Wen Liang Tan Junye Pan Yanqing Zhu Jiahui Chen Bingxin Duan Peiran Hou Min Hu Christopher R.Mc Neill Jianfeng Lu Yi-Bing Cheng 《Journal of Energy Chemistry》 2025年第9期477-484,I0013,共9页
Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic lo... Poly(3-hexylthiophene)(P3HT)is one of the most promising hole-transporting materials in the pursuit of efficient and stable perovskite solar cells due to its outstanding stability and low cost.However,the intrinsic low carrier density of P3 HT and poor contact between the P3HT/perovskite interface always lead to a low performance of the solar cell,while conventional chemical doping always makes the films unstable and limits the scalability.In this work,for the first time,we simultaneously enhanced the hole transporting properties of P3HT film and the interface of perovskite by doping it with a judiciously designed oxidized small molecule organic semiconductor.The organic salt not only can promote the lamellar crystallinity of P3HT to obtain better charge transport properties,but also reduce the defects of perovskite.As a result,we achieved champion efficiencies of 23.0%for small-area solar cells and 18.8%for larger-area modules(48.0 cm^(2)).This efficiency is the highest value for P3HT-based perovskite modules.Moreover,the solar cells show excellent operational stability,retaining over 95%of their initial efficiencies after1200 h of continuous operation. 展开更多
关键词 P3HT doping Perovskite solar cells Perovskite solar modules Small molecule organic semiconductor Interface passivation
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Electronic modulation induced by coupling RuO_(2)with electron-donating Co_(3)O_(4)for high-active and long-life rechargeable Zn-air batteries
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作者 Xuena Ma Zhangxin Xu +4 位作者 Mingyang Liu Panzhe Qiao Qi Li Ruihong Wang Baojiang Jiang 《Journal of Energy Chemistry》 2025年第2期99-109,I0004,共12页
Electronic-state modulation strategy offers great potential in designing RuO_(2)-based bifunctionalelectrocatalysts for rechargeable Zn-air batteries(ZABs).Various three-dimensional(3D)transition metal oxides are atte... Electronic-state modulation strategy offers great potential in designing RuO_(2)-based bifunctionalelectrocatalysts for rechargeable Zn-air batteries(ZABs).Various three-dimensional(3D)transition metal oxides are attempted to couple with RuO_(2)for constructing an appropriate Ru—O—M interface.This work aims to construct Co_(3)O_(4)-RuO_(2)heterostructures on carbon sheets(Co_(3)O_(4)/RuO_(2)/NCNS)for boosting electronic transfer and regulation.Experiments and theoretical calculations identify the electronic transfer from Co_(3)O_(4)to RuO_(2)that modulates the electronic structure of metal surfaces/interfaces.Specifically,it leads to the increase in Co3+content,electron-rich state at RuO_(2)surface and electronic accumulation at interfaces.Moreover,this electronic-state modulation optimizes the d-band center in Co_(3)O_(4)/RuO_(2)that lowers the reaction barriers and endows interfaces as the biggest contributor to oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)performance,The Co_(3)O_(4)/RuO_(2)/NCNS shows a quite low potential difference of 0.62 V and remarkable durability for ORR/OER.Co_(3)O_(4)/RuO_(2)/NCNS-assembled ZABs exhibit an excellent specific capacity of 818.3 mA h g^(-1)and a superior lifespan over 750 h. 展开更多
关键词 Co_(3)O_(4)-RuO_(2)heterostructure Electronic modulation Reaction energy barrier Zn-air battery Charge-discharge stability
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Influence of casting module on corrosion behavior of Mg-11Gd-3Y alloy 被引量:2
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作者 刘贤斌 单大勇 +2 位作者 宋影伟 陈荣石 韩恩厚 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期903-911,共9页
The influences of two kinds of casting modules of metal casting (MC) and expandable pattern casting (EPC) on the corrosion behavior of Mg-11Gd-3Y alloy were studied by electrochemical measurements, scanning electr... The influences of two kinds of casting modules of metal casting (MC) and expandable pattern casting (EPC) on the corrosion behavior of Mg-11Gd-3Y alloy were studied by electrochemical measurements, scanning electron microscopy (SEM) observation, X-ray diffractometry (XRD) and X-ray photoelectron spectroscopy (XPS) analysis. It is found that the quantity of the Mg 24 (Gd, Y) 5 phase in MC is more than that in EPC due to the cooling rate. There is more alloying element dissolved in the matrix compared with MC. For EPC, the galvanic corrosion effect between the matrix and the Mg 24 (Gd, Y) 5 phase decreases and the corrosion resistance increases compared with the MC. The chief corrosion mode for Mg-11Gd-3Y alloy is pitting corrosion because most of the alloying elements are transformed into intermetallic phases. The average corrosion rate of the MC alloy in the immersion test is five times higher than that of EPC alloy and yttrium is present in the product film, which will provide increased protection for Mg-11Gd-3Y alloy. The electrochemical measurements and immersion test show that the EPC process increases the corrosion resistance compared with the MC Mg-11Gd-3Y alloy. 展开更多
关键词 Mg-11Gd-3Y alloy corrosion behavior casting module expandable pattern casting metal casting
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LiNbO_(3)晶体沿光轴方向加电场时的横向电光调制特性计算
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作者 黄水平 钱小青 《物理与工程》 2025年第1期196-201,共6页
本文从LiNbO_(3)晶体的折射率椭球方程和电光系数矩阵出发,对LiNbO_(3)晶体沿光轴方向加电场时的横向电光调制特性进行了计算与分析。结果表明,由于自然相位差的存在,LiNbO_(3)晶体的电光调制曲线不一定经过坐标原点。同时,晶体的电光... 本文从LiNbO_(3)晶体的折射率椭球方程和电光系数矩阵出发,对LiNbO_(3)晶体沿光轴方向加电场时的横向电光调制特性进行了计算与分析。结果表明,由于自然相位差的存在,LiNbO_(3)晶体的电光调制曲线不一定经过坐标原点。同时,晶体的电光调制曲线对通光方向在y、z轴决定平面内的微小偏离非常敏感,导致实验中零电压下正弦调制信号的解调信号波形在实验中具有随机性,但这并不影响LiNbO_(3)晶体半波电压的测量结果。这些结果及结论不仅能很好地解答学生在实验中存在的疑惑,对实验教师和相关实验人员也有一定参考作用。 展开更多
关键词 LiNbO_(3)晶体 电光效应 横向电光调制 调制曲线
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基于改进Deeplabv 3+模型的遥感影像地物语义分割方法研究 被引量:2
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作者 南国君 王敏 +2 位作者 都海波 谢枫 许水清 《控制与决策》 北大核心 2025年第2期423-431,共9页
面向电力自动化领域,针对在遥感影像关键地物信息提取过程中,地物类别分布不均衡和不同域场景风格差异较大带来提取效果一般的问题,采用一种改进Deeplabv 3+语义分割网络.首先,在主干网络ResNet 101中使用IBN模块,用于增强模型对风格差... 面向电力自动化领域,针对在遥感影像关键地物信息提取过程中,地物类别分布不均衡和不同域场景风格差异较大带来提取效果一般的问题,采用一种改进Deeplabv 3+语义分割网络.首先,在主干网络ResNet 101中使用IBN模块,用于增强模型对风格差异较大的遥感影像的泛化能力,同时为了进一步提高模型的分割精度,在网络中加入SE模块,加强重要的通道信息,缓解信息丢失问题;然后,损失函数使用Dice+Focal的联合损失函数,Dice Loss损失函数可缓解类别分布不均衡对小目标提取的影响,Focal Loss损失函数不仅可以使得模型更关注分类困难的目标,还可以改善Dice Loss造成的网络训练的不稳定.实验结果表明:所提出改进Deeplabv 3+与原Deeplabv 3+模型相比,将F 1-Score提高了7.78%,Intersection over Union提高了5.78%;与其他主流语义分割模型(包括FCN、UNet、SegNet)相比,所提出改进Deeplabv 3+在地物提取中实现了更好的分割精度. 展开更多
关键词 语义分割 Deeplabv 3+ IBN模型 遥感影像 损失函数 地物提取
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g-C_(3)N_(4)的改性及其在光催化领域的研究进展 被引量:1
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作者 匡代洪 张佳睿 +2 位作者 杨佳东 阿瓦拜克力·肉苏里 谢瑜 《精细化工》 北大核心 2025年第7期1418-1433,共16页
半导体光催化技术作为人工光合作用,可缓解当前全球面临的环境污染和能源短缺危机,近年来已成为热门研究方向。石墨相氮化碳(g-C_(3)N_(4))是一种二维层状结构半导体材料,制备方法简单,具有良好的可见光响应能力,是当前光催化材料的研... 半导体光催化技术作为人工光合作用,可缓解当前全球面临的环境污染和能源短缺危机,近年来已成为热门研究方向。石墨相氮化碳(g-C_(3)N_(4))是一种二维层状结构半导体材料,制备方法简单,具有良好的可见光响应能力,是当前光催化材料的研究热点。直接聚合含氮前驱体制备的g-C_(3)N_(4)光催化性能较差,需对g-C_(3)N_(4)进行性能调控。该文简单介绍了g-C_(3)N_(4)的主要制备方法;阐述了g-C_(3)N_(4)的改性方法,包括提升结晶度、构建异质结、调控形貌、缺陷工程,并总结了g-C_(3)N_(4)在光催化领域的应用,包括降解有机污染物、分解水制氢、生产H_(2)O_(2)、还原CO_(2);最后,对g-C_(3)N_(4)的未来发展进行了展望,在持续提升g-C_(3)N_(4)光催化性能的同时,应更多考虑实际工业化生产面临的相关设计问题,并将熔融盐法制备高结晶g-C_(3)N_(4)深入探究、g-C_(3)N_(4)基异质结体系的搭建、g-C_(3)N_(4)中光生载流子的分离机制明确、反应物在g-C_(3)N_(4)表面的吸脱附和氧化还原反应的作用机制分析、可回收g-C_(3)N_(4)基光催化剂研究5个方面作为重点发展方向。 展开更多
关键词 光催化技术 g-C_(3)N_(4) 半导体材料 性能调控 改性方法
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^(3)He正比计数管集成核电子学器件研制与测试
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作者 时亚茹 张春雷 刘晓波 《核电子学与探测技术》 北大核心 2025年第9期1332-1344,共13页
本文介绍了一款高集成、紧凑型的^(3)He正比计数管核电子学读出模块的研制及测试验证。该模块采用一体化紧凑型设计,内部集成了高低压电源、电荷灵敏前置放大器、滤波成形放大模块、脉冲幅度甄别模块。可实现对探测器输出信号的放大、... 本文介绍了一款高集成、紧凑型的^(3)He正比计数管核电子学读出模块的研制及测试验证。该模块采用一体化紧凑型设计,内部集成了高低压电源、电荷灵敏前置放大器、滤波成形放大模块、脉冲幅度甄别模块。可实现对探测器输出信号的放大、滤波整形与幅度甄别,支持同时输出高斯脉冲模拟信号和TTL逻辑脉冲信号,能够实现对中子信号的能谱测量和计数测量,且具有TTL输入加和功能以实现多个探测器信号级联。该模块整体尺寸为Φ37.8 mm×88 mm,可与^(3)He/BF_(3)正比计数管直接匹配,供电仅需低压12 V输入电源,同时具备高压、增益、脉宽和甄别阈关键参数调节功能。使用中子源搭建测试平台对模块的技术性能和环境适应性进行了测试,并应用于中子探测装置的实验测量,成功实现了^(252)Cf中子源强的精确标定和裂变中子衰减时间的测量。 展开更多
关键词 ^(3)He正比计数管 集成核电子学模块 中子测量 放大甄别
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基于Production Module 3D数控铣削仿真技术在钛合金主吊挂加工中的应用 被引量:3
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作者 吴东华 邓志刚 +2 位作者 张德纯 赵万岳 丁代华 《机械工程师》 2021年第11期149-152,155,共5页
在钛合金主吊挂支架的铣削过程中,采用Production Module 3D软件对数控程序、材料、刀具及工件的综合分析,得到了在整个数控程序下的温度峰值、进给力、切削力及材料去除率等数据。然后采用完善数控程序中的吃刀量、切削速度及进给量来... 在钛合金主吊挂支架的铣削过程中,采用Production Module 3D软件对数控程序、材料、刀具及工件的综合分析,得到了在整个数控程序下的温度峰值、进给力、切削力及材料去除率等数据。然后采用完善数控程序中的吃刀量、切削速度及进给量来使加工过程中温度、切削力等符合要求,使负载平衡,降低振动。最终刀具的使用寿命提高20%,加工周期降低22%。 展开更多
关键词 钛合金 铣削 Production module 3D
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硫掺杂Cu_(3)Mo_(2)O_(9)负极材料结构设计及其电化学储锂特性分析
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作者 王金凯 刘智 王红康 《电工技术学报》 北大核心 2025年第21期7076-7091,共16页
铜钼基氧化物因其低成本和高理论容量而被认为是锂离子电池理想的负极材料之一,但其仍然存在体积变化大和固有电导率低等问题,这会使电池容量快速衰减,倍率性能变差。对此,该文通过溶剂热法合成了一种新型空心结构Cu_(3)Mo_(2)O_(9)微米... 铜钼基氧化物因其低成本和高理论容量而被认为是锂离子电池理想的负极材料之一,但其仍然存在体积变化大和固有电导率低等问题,这会使电池容量快速衰减,倍率性能变差。对此,该文通过溶剂热法合成了一种新型空心结构Cu_(3)Mo_(2)O_(9)微米球,并利用简单原位热解工艺设计了一种硫掺杂Cu_(3)Mo_(2)O_(9)单晶材料(S-CMO)。通过调节退火温度,实现了相结构和形貌结构的协同调控,从而提高了电化学储锂性能。S-CMO-450电极表现出高储锂比容量、长循环稳定性和快倍率充放性能,在0.2 A/g下其可逆容量高达894.5 mA·h/g,即使在0.5 A/g大电流密度下历经250次循环后,其容量仍能保持733.1 mA·h/g。其电化学储锂性能得益于硫掺杂改性策略和CuMoO_(4)、CuO、Cu_(3)Mo_(2)O_(9)异质结构的多元协同作用。硫掺杂可为电极提供更多的电化学活性位点,提高电池储锂容量;异质结构多元协同作用则由于其不同的电化学反应电势可有效地缓解电极在循环过程中较大的体积膨胀,增强循环性能。 展开更多
关键词 硫掺杂 Cu_(3)Mo_(2)O_(9) 结构调控 电化学储锂
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基于Si_(3)N_(4)陶瓷层的SiC功率模块封装结构优化
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作者 陈姣 郑亮 《机械研究与应用》 2025年第1期52-55,60,共5页
在第三代宽禁带半导体中,Si_(3)N_(4)陶瓷因兼具高强度和高热导率而成为最具潜力的绝缘性散热基底材料。该文根据多准则决策法(考虑结温、热阻、热膨胀系数CTE不匹配等),采用热-应力耦合仿真探究不同焊层和基底材料的替换对模块与Si_(3)... 在第三代宽禁带半导体中,Si_(3)N_(4)陶瓷因兼具高强度和高热导率而成为最具潜力的绝缘性散热基底材料。该文根据多准则决策法(考虑结温、热阻、热膨胀系数CTE不匹配等),采用热-应力耦合仿真探究不同焊层和基底材料的替换对模块与Si_(3)N_(4)陶瓷层组合热特性和可靠性的综合影响。结果表明,与Si_(3)N_(4)陶瓷层组合中热特性和可靠性结合效果最优的组合为纳米银焊层和CuW基底。然后采用温度循环仿真法验证优化后的模型,结果显示,优化后的模型的平均应力下降16.6%,平均第一主应变下降10.2%。此结论为Si_(3)N_(4)陶瓷基板与其它部件结合使用的可靠性评价提供一定的参考。 展开更多
关键词 功率模块 Si_(3)N_(4)陶瓷层 温度循环 可靠性
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Optical transmitter module with hybrid integration of DFB laser diode and proton-exchanged LiNbO_(3)modulator chip
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作者 Xuyang Wang He Jia +2 位作者 Junhui Li Yumei Guo Yu Liu 《Journal of Semiconductors》 EI CAS CSCD 2022年第6期34-39,共6页
In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fib... In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical isolator.The whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output efficiency.After a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was obtained.The optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured. 展开更多
关键词 optical transmitter module hybrid integration DFB laser chip LiNbO3 modulator chip
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3-D Magnetic Sensor Module for Locating and Tracking MEMS Swallowable Capsule Based on Scalar Form of Magnetic Dipole Model 被引量:2
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作者 WU Xu-dong PENG Cheng-lin HOU Wen-sheng ZHENG Xiao-lin FANG Xing 《Chinese Journal of Biomedical Engineering(English Edition)》 2007年第2期79-86,共8页
MEMS swallowable capsule is a novel technology in the non-invasive surgery. This technology provides a way to diagnose directly into the deep intestinal where the traditional invasive technology implemented, such as X... MEMS swallowable capsule is a novel technology in the non-invasive surgery. This technology provides a way to diagnose directly into the deep intestinal where the traditional invasive technology implemented, such as X-Ray, endoscopy. It is a key for us to locate and track the position of a MEMS capsule in clinical applications. To solve this problem, we implemented a magnetic sensor module based on the scalar form of the magnetic dipole model,which was designed with very small size (5.2 * 2. 1 * 1.2 em) and easy to assemble to satisfy the system requirement. Here we discuss in detail the principle of magnetic dipole model, rules of selecting sensor and functions of the module. Some trials are established to test the characteristic of the module. The results of the Cm experiment demonstrates that the module follows the rules of the new magnetic dipole model form. 展开更多
关键词 sealar form of magnetic dipole model 3-D magnetic sensor module
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补阳还五汤调控JAK2/STAT3信号通路对db/db小鼠肾小管上皮细胞线粒体稳态的调节作用
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作者 娄菲菲 张学琴 +2 位作者 田小超 王月华 陈志强 《中国实验方剂学杂志》 北大核心 2025年第23期1-11,共11页
目的:观察补阳还五汤调控Janus激酶信号转导器2(JAK2)/转录的信号转导和激活因子3(STAT3)信号通路对自发性糖尿病db/db小鼠肾小管上皮细胞线粒体稳态的调节作用。方法:db/db小鼠30只随机分为3组(每组10只),分别为模型组、补阳还五汤组(2... 目的:观察补阳还五汤调控Janus激酶信号转导器2(JAK2)/转录的信号转导和激活因子3(STAT3)信号通路对自发性糖尿病db/db小鼠肾小管上皮细胞线粒体稳态的调节作用。方法:db/db小鼠30只随机分为3组(每组10只),分别为模型组、补阳还五汤组(21.47 g·kg^(-1))、恩格列净组(10 mg·kg^(-1));同时,以db/m小鼠(n=10)作为正常组。予以相应药物12周后,检测小鼠肾质量/体质量(KW/BW)值、24 h尿蛋白定量(24 h UTP)、尿微量蛋白肌酐比(UACR)、血肌酐(SCr)、N-乙酰-β-D-氨基葡萄糖苷酶(NAG)、中性粒细胞明胶酶相关脂质运载蛋白(NGAL)、血清胱抑素C(Cys C)、肾损伤分子1(KIM-1);苏木素-伊红(HE)染色观察小鼠肾组织病理形态学改变;蛋白免疫印迹法(Western blot)及免疫荧光(IF)检测小鼠KIM-1及凋亡相关蛋白、炎症因子、线粒体动力学蛋白及JAK2/STAT3通路相关蛋白的表达;酶联免疫吸附测定法(ELISA)检测小鼠超氧化物歧化酶(SOD)、丙二醛(MDA)水平,实时荧光定量聚合酶链式反应(Real-time PCR)检测小鼠肾组织中JAK2、STAT3 mRNA的表达。结果:与正常组比较,模型组小鼠KW/BW明显升高(P<0.05),24 h UTP、UACR明显升高(P<0.05,P<0.01),尿液KIM-1、NAG、NGAL、Cys C显著升高(P<0.01),HE染色可见模型组小鼠出现肾小球体积变大,肾小管扩张、空泡变性,血清白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)显著升高(P<0.01),B细胞淋巴瘤-2(Bcl-2)相关X蛋白(Bax)、切割的胱天蛋白酶-3(cleaved Caspase-3)表达显著升高(P<0.01)、Bcl-2显著下降(P<0.01),血清MDA明显升高(P<0.05),SOD明显下降(P<0.05),线粒体动力相关蛋白1(DRP1)、分裂蛋白1(FIS1)表达显著升高(P<0.01),融合蛋白OPA1、MFN2显著降低(P<0.01),p-JAK2及p-STAT3表达显著增高(P<0.01);与模型组比较,补阳还五汤组、恩格列净组小鼠KW/BW差异无统计学意义,24 h UTP、UACR、尿液KIM-1、NAG、NGAL、Cys C有不同程度下降(P<0.05,P<0.01),IL-6、TNF-α表达有所下降,Bax、cleaved Caspase-3显著降低(P<0.01),Bcl-2显著升高(P<0.01),MDA明显下调(P<0.05,P<0.01),SOD显著升高(P<0.01),DRP1、FIS1表达显著降低(P<0.01),视神经萎缩蛋白1(OPA1)、线粒体融合蛋白2(MFN2)明显升高(P<0.05,P<0.01),p-JAK2、p-STAT3表达显著下调(P<0.01),Real-time PCR呈现出一致趋势,小鼠肾脏病理损伤有所减轻。结论:补阳还五汤能够减轻db/db小鼠肾脏损伤及细胞凋亡,并可改善肾脏炎症及氧化应激状态,其机制可能与抑制JAK2/STAT3信号通路的过度激活,进而维持线粒体动力学稳态相关。 展开更多
关键词 补阳还五汤 肾小管上皮细胞 线粒体 Janus激酶信号转导器2(JAK2)/转录的信号转导和激活因子3(STAT3)通路
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Dy^(3+)/Tm^(3+)共掺石榴石镓酸盐粉末的制备及其性能研究
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作者 林子康 刘杨 +3 位作者 洪智 刘雯琪 连政 黄建辉 《中国稀土学报》 北大核心 2025年第6期1179-1188,共10页
W-LED作为第四代照明光源,广泛应用在家居照明、医学照明等领域,近紫外激发单一基质荧光粉逐渐成为研究热点。本文采用高温固相法制备了一系列稀土离子激活荧光粉:Y_(3)Sc_(2)Ga_(3)O_(12):xDy^(3+)和Y_(3)Sc_(2)Ga_(3)O_(12):0.06Dy^(3... W-LED作为第四代照明光源,广泛应用在家居照明、医学照明等领域,近紫外激发单一基质荧光粉逐渐成为研究热点。本文采用高温固相法制备了一系列稀土离子激活荧光粉:Y_(3)Sc_(2)Ga_(3)O_(12):xDy^(3+)和Y_(3)Sc_(2)Ga_(3)O_(12):0.06Dy^(3+)/yTm^(3+)。通过测试样品的XRD及荧光光谱、荧光寿命和SEM等性能对样品的物相、结构及发光性能进行了表征,并对其能量传递机制和CIE坐标进行了研究。XRD分析表明Dy^(3+)和Tm^(3+)均成功取代Y^(3+)进入基质晶格。荧光光谱结果表明:Y_(3)Sc_(2)Ga_(3)O_(12):xDy^(3+)在监测波长为582 nm下时的最佳激发波长为351 nm;用最佳激发波长激发时Y_(3)Sc_(2)Ga_(3)O_(12):xDy^(3+)荧光粉发射黄光和蓝光,其发光强度随着Dy^(3+)的浓度增加呈现先增大后减小的规律,Y_(3)Sc_(2)Ga_(3)O_(12):0.06Dy^(3+)发光强度最好。根据Dy^(3+)和Tm^(3+)的激发光谱,选取364 nm波长激发Y_(3)Sc_(2)Ga_(3)O_(12):0.06Dy^(3+)/yTm^(3+)荧光粉发光,通过调控Tm^(3+)的掺杂比例实现Y_(3)Sc_(2)Ga_(3)O_(12):0.06Dy^(3+)/yTm^(3+)最强发光并且发光颜色可调。通过监测不同浓度Tm^(3+)掺杂下Dy^(3+)的荧光寿命,验证了Dy^(3+)/Tm^(3+)之间存在能量传递。色坐标分析结果表明改变Tm^(3+)的掺杂比例,可以实现发光颜色的调节,发光颜色从黄绿色到蓝紫色变化,其中Y_(3)Sc_(2)Ga_(3)O_(12):0.06Dy^(3+)/0.05Tm^(3+)荧光粉的CIE色坐标为(0.3302,0.3401),最接近标准白光点(0.333,0.333)。实验结果表明:通过调节Dy^(3+)/Tm^(3+)掺杂比,Y_(3)Sc_(2)Ga_(3)O_(12):Dy^(3+)/Tm^(3+)荧光粉可实现白光发射,在W-LED照明领域具有很好的应用价值。 展开更多
关键词 Dy^(3+)/Tm^(3+)共掺杂 光谱性能 荧光调控
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MicroRNAs as novel molecular targets of green tea polyphenol epigallocatechin-3-gallate(EGCG):relevance and importance to nutrition sciences and cancer prevention
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作者 Yu Li Qingping Dou +5 位作者 Bo Li Yongli Wang Xiushan Wang Hui Guan Dapeng Li Feng Li 《Food Science and Human Wellness》 2025年第11期4308-4322,共15页
MicroRNAs(miRNAs)are a class of single-stranded and non-coding endogenous RNAs with 18−25 nucleotides in length.By binding to the complementary sequences in the 3′-untranslated region(3′-UTR)of protein coding genes,... MicroRNAs(miRNAs)are a class of single-stranded and non-coding endogenous RNAs with 18−25 nucleotides in length.By binding to the complementary sequences in the 3′-untranslated region(3′-UTR)of protein coding genes,miRNAs regulate posttranscriptionally the mRNA expression of target genes and enzymes involved in various biological processes.The application of high-throughput sequencing,bioinformatics analysis,and novel detection methods has high-lighted promising roles of miRNAs as both novel biomarkers for tumor diagnosis and critical regulators involved in almost all stages of carcinogenesis including cancer initiation,promotion and progression.Epigallocatechin-3-gallate(EGCG),the most investigated active catechin in green tea,has been linked to various health-promoting benefits including chemoprevention and treatment of cancers.In this review,we first present a brief description of EGCG and its major metabolic pathway.It is followed by reviewing the roles of EGCG in the modulation of oncogenic and tumor suppressing miRNAs in some common cancers.These findings suggest that the capacity of EGCG to regulate expression of specific miRNAs provides insights of its new mechanisms of action underlying its chemopreventive and potential beneficial activities against various cancers. 展开更多
关键词 Epigallocatechin-3-gallate microRNA Cancer modulation CHEMOPREVENTIVE
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血清G蛋白信号调节因子2、适配器相关蛋白复合物3亚基mu2与早期结直肠癌病人临床病理特征及预后的相关性分析
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作者 孙宇 郝立政 胡晓立 《临床外科杂志》 2025年第6期623-627,共5页
目的探讨血清G蛋白信号调节因子2(GPSM2)、适配器相关蛋白复合物3亚基mu2(AP3M2)与早期结直肠癌(CRC)病人临床病理特征及其术后预后的相关性。方法2020年1月~2021年12月治疗的早期CRC病人142例(CRC组)和结直肠息肉病人96例(良性病变组)... 目的探讨血清G蛋白信号调节因子2(GPSM2)、适配器相关蛋白复合物3亚基mu2(AP3M2)与早期结直肠癌(CRC)病人临床病理特征及其术后预后的相关性。方法2020年1月~2021年12月治疗的早期CRC病人142例(CRC组)和结直肠息肉病人96例(良性病变组),同期健康志愿者80例(对照组)。采用RT-qPCR检测血清GPSM2、AP3M2水平;采用Kaplan-Meier生存曲线分析血清GPSM2、AP3M2表达与CRC病人预后的关系;Cox回归分析影响CRC病人预后的危险因素;ROC曲线分析血清GPSM2、AP3M2对CRC病人预后的预测价值。结果良性病变组和CRC组血清GPSM2、AP3M2水平高于对照组,且CRC组高于良性病变组,差异有统计学意义(P<0.05)。CRC病人血清GPSM2、AP3M2水平与其分化程度有关(P<0.05)。GPSM2、AP3M2低表达病人3年生存率均高于GPSM2、AP3M2高表达病人(85.29%、87.14%vs 67.57%、65.28%)(Log rankχ^(2)=7.205、10.800,P<0.05)。低分化程度以及血清GPSM2、AP3M2水平升高是影响CRC病人预后的危险因素(P<0.05)。血清GPSM2、AP3M2联合预测CRC病人预后的AUC为0.903(Z_(二者联合-GPSM2)=2.882、Z_(二者联合-AP3M2)=3.322,P<0.05),敏感性为88.24%,特异性为82.41。结论CRC病人血清GPSM2、AP3M2水平升高,与分化程度及预后密切相关,二者联合预测CRC病人预后具有较高的临床价值。 展开更多
关键词 结直肠癌 G蛋白信号调节因子2 适配器相关蛋白复合物3亚基mu2 临床病理特征 预后
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Innovative rotary swaging method drives high performance of n-type Bi_(2)(Te,Se)_(3)thermoelectrics
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作者 Liya Miao Xiang Lu +11 位作者 Qiang Zhang Xiaojian Tan Lidong Chen Kaikai Pang Ruyuan Li Qianqian Sun Min Wang Peng Sun Jiehua Wu Guoqiang Liu Zhenlun Song Jun Jiang 《Journal of Materials Science & Technology》 2025年第20期114-122,共9页
The thermoelectric transport of n-type Bi_(2)Te_(3) heavily depends on grain alignment,causing perfor-mance limitations that severely restrict the demand for low-grade waste heat recovery.Here,the n-type Bi_(2)Te_(2.7... The thermoelectric transport of n-type Bi_(2)Te_(3) heavily depends on grain alignment,causing perfor-mance limitations that severely restrict the demand for low-grade waste heat recovery.Here,the n-type Bi_(2)Te_(2.7)Se_(0.3) material with a certain textured structure is prepared by an innovative rotary swag-ing method.It is found that various defects including Te vacancies,dislocations,and grain boundaries significantly strengthen the phonon scattering.With an obviously suppressed thermal conductivity and well-maintained carrier mobility,the obtained rods extending up to several tens of centimeters achieve a peak ZT of 1.2 at 450 K and an average ZT of 1.0(300-550 K),with Vickers hardness and compressive strength increased to 0.42 GPa and 52.6 MPa,respectively.Moreover,the assembled 17-pair thermoelec-tric module achieves a competitive conversion efficiency of up to 6.3% and a high output power of 0.93 W at a temperature difference of 250 K.This study develops an effective strategy for synergistically en-hancing the thermoelectric and mechanical properties of n-type Bi_(2)(Te,Se)_(3). 展开更多
关键词 Bi_(2)(TeSe)_(3) Rotary swaging Evolutionary microstructure Thermoelectric module
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Tumor-derived exosomal miR-425-5p and miR-135b-3p enhance colorectal cancer progression through immune suppression and vascular permeability promotion
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作者 Chun-Zai Feng Si-Quan Zhong +3 位作者 Shao-Wei Ye Zheng Zheng Hao Sun Shi-Hai Zhou 《World Journal of Gastrointestinal Oncology》 2025年第6期423-438,共16页
BACKGROUND Colorectal cancer(CRC)is a leading cause of cancer-related morbidity and mor-tality globally.Exosomal microRNAs(miRNAs)are known to modulate tumor progression by influencing immune responses and vascular dy... BACKGROUND Colorectal cancer(CRC)is a leading cause of cancer-related morbidity and mor-tality globally.Exosomal microRNAs(miRNAs)are known to modulate tumor progression by influencing immune responses and vascular dynamics.However,the roles of specific exosomal miRNAs,such as miR-425-5p and miR-135b-3p,in CRC remain unclear.AIM To explore the specific roles and underlying mechanisms of exosomal miR-425-5p and miR-135b-3p in CRC progression.METHODS Differentially expressed miRNAs were identified through microarray analysis of exosomes isolated from CRC tissues and adjacent normal mucosa.Functional roles of miR-425-5p and miR-135b-3p were evaluated in vitro using macrophage polarization,T cell differentiation,and vascular permeability assays,as well as in vivo tumor formation and metastasis experiments in nude mice.Validation expe-riments were performed using CRC cell lines(HCT116 and SW620).RESULTS Exosomal miR-425-5p and miR-135b-3p were significantly upregulated in CRC compared to normal tissues.Functional studies revealed that miR-425-5p promo-tes macrophage M2-like polarization and suppresses T cell proinflammatory responses,while miR-135b-3p enhances vascular permeability and angiogenesis.Inhibition of these miRNAs in CRC cell-derived exosomes significantly supp-ressed tumor growth and metastasis in nude mice,reprogramming the tumor microenvironment toward reduced angiogenesis and enhanced immune acti-vation.Combined inhibition of both miRNAs resulted in the most pronounced effects.CONCLUSION Exosomal miR-425-5p and miR-135b-3p drive CRC progression by promoting immune suppression and vascular permeability.Their inhibition offers a promising strategy for modulating the tumor microenvironment and limiting CRC metastasis. 展开更多
关键词 Colorectal cancer EXOSOMES MiR-425-5p MiR-135b-3p Immune modulation Vascular permeability
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Design of RTD temperature acquisition module based on ADuCM361
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作者 PAN Yuting CHEN Yuchen +1 位作者 YUAN Zhiqiang TAN Hong 《International English Education Research》 2016年第1期51-52,共2页
Aiming at acquiring and processing requirements of temperature sensor signal on the industrial control spot, it designs a RTD module based on ADuCM361 microprocessor. It integrates two types of processors including A ... Aiming at acquiring and processing requirements of temperature sensor signal on the industrial control spot, it designs a RTD module based on ADuCM361 microprocessor. It integrates two types of processors including A -Y ADC with 24 bites high precision and ARM Cortex -M3 kernel with 32bites. Besides, it designs the hardware circuit and software flowchart of RTD temperature acquisition module. Programming practice proves that the model has many advantages concluding simple construction, strong practicability, low cost, wide measuring range, high precision, high reliability and so on. 展开更多
关键词 ADuCM361 microprocessor RTD temperature acquisition module A∑-ADC ARM Cortex?-M3 kernel
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二维Janus Ga_(2)SSe/β-Ga_(2)O_(3)异质结在双轴应变调控下的电子及光学特性
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作者 苗瑞霞 贾小坛 +1 位作者 牛佳美 晏杰 《材料导报》 北大核心 2025年第14期20-26,共7页
二维Janus过渡金属二硫族化物(MXY结构)已被用于与β-Ga_(2)O_(3)构建异质结来改善β-Ga_(2)O_(3)的光电性能,但是具有M2XY结构的Ⅲ-Ⅵ族Janus硫族化物与β-Ga_(2)O_(3)接触形成异质结的研究鲜有报道。本研究探索了Ga_(2)SSe/β-Ga_(2)O... 二维Janus过渡金属二硫族化物(MXY结构)已被用于与β-Ga_(2)O_(3)构建异质结来改善β-Ga_(2)O_(3)的光电性能,但是具有M2XY结构的Ⅲ-Ⅵ族Janus硫族化物与β-Ga_(2)O_(3)接触形成异质结的研究鲜有报道。本研究探索了Ga_(2)SSe/β-Ga_(2)O_(3)异质结的电子结构与光吸收特性,并研究了双轴应变对该异质结性能的影响。研究结果表明:(1)异质结Ga_(2)SSe(-Se)/β-Ga_(2)O_(3)相比于Ga_(2)SSe(-S)/β-Ga_(2)O_(3)有较低的隧穿势垒以及更高的传输效率;同时异质结在紫外光区域的光吸收能力显著增强。(2)双轴应变对异质结的带隙类型、载流子有效质量以及光吸收性能的影响较显著。在-8%到8%的双轴应变下,异质结带隙随应变的增大而减小,带隙值在0.2~1.43 eV较宽范围可调;异质结的电子有效质量从0.376 eV缓慢减小至0.258 eV,而空穴有效质量在压缩应变为-2%时发生骤降,说明压缩应变对空穴有效质量影响更显著;此外,在拉伸应变下,异质结的光吸收能力从红外到紫外区较压缩应变时明显增强。本研究不仅揭示了Ga_(2)SSe/β-Ga_(2)O_(3)异质结的优异性能,还为高性能光电器件的设计提供了新思路和理论支撑。 展开更多
关键词 β-Ga_(2)O_(3) Ⅱ型范德华异质结 双轴应变调控 光电特性
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