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Boosting the adsorption performance of ethanol on surface chemistry modified activated carbon fiber
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作者 Mengyan Wang Yuxuan Wang +6 位作者 Junhao Wang Yinghui Han Jianxiao Yang Suchan Yang Yuanxun zhang Peng Huo xin zhang 《Journal of Environmental Sciences》 2026年第1期178-186,共9页
As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This stud... As a potential adsorption material,it is still a challenge for activated carbon fiber(ACF)in efficient adsorption of ethanol due to its nonpolar surface,which is mainly emitted from the grain drying industry.This study prepared surface polarity-modified ACF using the heteroatom doping method.The modified ACF possessed a richer array of strongly polar oxygen/nitrogen-containing functional groups(primarily phenolic hydroxyl and lactone groups),a larger specific surface are1,and a more developed micropore structure.The adsorption capacities of ethanol for O-ACF and N-ACF were 4.110 mmol/g and 1.698 mmol/g,respectively,which were 11.3 times and 4.7 times those of unmodified ACF.This was a significant improvement over our previous work(0.363 mmol/g).The improvement of adsorption capacity for the N-ACF was mainly due to the higher specific surface are1,greater number of micropores(more adsorption sites)and abundant existence of defects,whereas,for O-ACF,the improvement mainly relied on the abundant presence of oxygen-containing functional groups on the surface.However,water had a negative effect on the adsorption of ethanol for the modified ACF due to competitive adsorption and the disappearance of capillary condensation.It was further revealed that the adsorption process of ethanol and water was quite different.It obeyed the linear driving force(LDF)model for ethanol adsorption,however,the intraparticle diffusion(IPD)model for water adsorption. 展开更多
关键词 Activated carbon fiber(ACF) Heteroatom doping Surface polarity-modified Polar functional groups Microporous filling Linear driving force(LDF) In-particle diffusion(IPD)
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P2RX1 Influences the Prognosis of Ph+/Ph-Like ALL through Energy and Calcium Metabolism
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作者 Xiangmei Ye Baoyi Yang +12 位作者 xin zhang Luyuan Yang Likun zhang Qin Ren Xiaobing Li Leiguang Feng Lanlan Wei Peng Song Yuqing Ye xin Lian Yujuan Gao Haidi Tang Zhiyu Liu 《Oncology Research》 2026年第1期279-296,共18页
Objectives:Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia and Philadelphia-like B-cell acute lymphoblastic leukemia(Ph+/Ph-like ALL)constitute the majority of relapsed/refractory B-ALL(R/R B-ALL)... Objectives:Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia and Philadelphia-like B-cell acute lymphoblastic leukemia(Ph+/Ph-like ALL)constitute the majority of relapsed/refractory B-ALL(R/R B-ALL)cases,highlighting an urgent need to discover new therapeutic targets.This study aims to elucidate the mechanisms underlying poor prognosis in Ph+/Ph-like ALL through transcriptome sequencing and functional cytological assays,with the goal of informing new clinical treatment strategies.Results:Transcriptomic analysis of Ph+/Ph-like ALL patients revealed that low expression of P2X Purinoceptor 1(P2RX1)was associated with unfavorable outcomes.Specifically,patients with poor prognosis and low P2RX1 expression exhibited downregulation of genes involved in energy and calcium metabolism pathways,along with upregulation of genes governing key cellular processes such as cell proliferation(e.g.,MYC),cell cycle progression(e.g.,CCND2),and apoptosis inhibition(e.g.,DASP6).Cellular experiments demonstrated that SUP-B15 cells overexpressing P2RX1 displayed elevated intracellular levels of ATP,calcium,and glucose,together with enhanced glycolytic capacity,compared to empty vector controls.Treatment of SUP-B15 cells with dexamethasone(Dex),Imatinib,or their combination significantly suppressed proliferation and promoted apoptosis,which was accompanied by increases in intracellular ATP,calcium,and glucose.Moreover,exogenous ATP administration(a P2RX1 agonist)enhanced apoptosis and inhibited proliferation in control cells.Conversely,treatment with NF449(a P2RX1 inhibitor)increased proliferation in both P2RX1-overexpressing and control SUP-B15 cells.Conclusion:Our findings indicate that P2RX1 may exert this function through modulating energy metabolism and calcium homeostasis,resulting in elevated intracellular calcium levels.Sustained elevation of calcium promotes apoptosis,whereas exogenous ATP activates P2RX1,enhances calcium influx,and attenuates the suppression of apoptosis associated with P2RX1 underexpression,ultimately correlating with improved treatment response. 展开更多
关键词 Philadelphia chromosome-positive acute lymphoblastic leukemia(Ph+ALL) Philadelphia chromosome-like B-cell acute lymphoblastic leukemia(Ph-like ALL) transcriptome sequencing P2X purinoceptor 1
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Geochemical and geochronological studies of the Aketas granite from Fuyun County, Xinjiang: the implications of the petrogenesis and tectonic setting 被引量:3
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作者 Xiaofeng Wei xin zhang +3 位作者 Jiuhua Xu Rufu Ding Guorui zhang Yong Tang 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2015年第4期579-591,共13页
As the wall rock of the Aketas gold deposit,the Aketas granite is about 45 km away from Fuyun County, Xinjiang Province. The zircon weighted mean U–Pb age of the Aketas granite is 309.0 ± 4.7 Ma, indicating that... As the wall rock of the Aketas gold deposit,the Aketas granite is about 45 km away from Fuyun County, Xinjiang Province. The zircon weighted mean U–Pb age of the Aketas granite is 309.0 ± 4.7 Ma, indicating that the Aketas granite was emplaced during the late Carboniferous. The Aketas granite belongs to the High-K calcalkaline series, with Si O2 content from 63.00 to 68.20 %,K2 O content from 3.06 to 4.49 % and Na2 O content from4.14 to 6.02 %. The Alkaline Ratio(AR) of the Aketas granite is high, from 1.89 to 3.47, and is 2.95 on average.The Aketas granite has lowPREE(92.42–122.73 ppm)and highPLREE/PHREE ratios(6.54–11.88). For the trace elements, the Aketas granite is enriched in LILE(Rb,U, Th, K) and incompatible elements, and marked depleted in HFSE(Nb, Ta, P, Ti). The geochemical characteristics of the Aketas granite suggest that it is a typical I-type and volcanic arc granite, and that the crystallization of clinopyroxene and hornblende is notable during the magmatic evolution. In combination with the regional tectonic studies, we propose that the emplacement of the Aketas granite implies the Altai and East Junggar area was still dominated by a subduction system at *309 Ma. 展开更多
关键词 花岗岩 地球化学 同位素年代学 富蕴县 构造背景 新疆 高钾钙碱性系列 成因
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Effect of cyclovirobuxine D on human growth-associated protein 43 and neurocan expression in ischemic brain tissue of stroke-prone renovascular hypertensive rats 被引量:1
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作者 Feng Tan Wei Gu +6 位作者 Saiying Wan Haike Wu Jinliang Wang Jingbo Sun Jiamao Cheng xin zhang Renfeng Huang 《Neural Regeneration Research》 SCIE CAS CSCD 2008年第4期394-397,共4页
BACKGROUND: Experimental data indicate that human growth-associated protein 43 mRNA expression coincides with axonal growth during nerve ganglion development; while neurocan, secreted from astrocytes, can inhibit spr... BACKGROUND: Experimental data indicate that human growth-associated protein 43 mRNA expression coincides with axonal growth during nerve ganglion development; while neurocan, secreted from astrocytes, can inhibit sprouting and elongation of the axonal growth cone. OBJECTIVE: To verify regulatory effects of cyclovirobuxine D (CVB-D) extracted from Chinese box branchlet on human growth-associated protein 43 (GAP-43), and neurocan expression in brain tissue of stroke-prone renovascular hypertensive (RHRSP) rats, at different time points after cerebral ischemia/reperfusion. DESIGN: Randomized grouping design and controlled animal study. SETTING: This study was performed at the Center of Guangdong Hospital of Traditional Chinese Medicine (a national key laboratory) from March 2003 to September 2006. MATERIALS: 100 healthy male Sprague-Dawley rats, aged 2 3 months and weighing 90-120 g, were selected for this study. CVB-D was provided by Nanjing Xiaoying Pharmaceutical Factory (Batch number: 307701). METHODS: The initial tip of renal arteries was clamped bilaterally for 10 weeks to establish the RHRSP model. 100 RHRSP rats were randomly divided into 4 groups: naive group (n = 10), sham surgery group (n = 10), CVB-D group (n = 40), and lesion group (n = 40). Rats in the naive group did not undergo any treatment, and cervical vessels of rats in the sham surgery group were exposed, but not blocked. The right middle cerebral artery of rats in the CVB-D group and lesion group were occluded to establish cerebral ischemia. Rats in the CVB-D group were intraperitoneally injected with CVB-D (6.48 mg/kg) every day and with saline (1.5 mL/injection) twice a day. Rats in the lesion group were intraperitoneally injected with saline (2 mL/injection). MAIN OUTCOME MEASURES: Immunohistochemistry was applied to detect GAP-43 and neurocan expression in the ischemic penumbra region of CVB-D and lesion brains at 2 hours post-cerebral ischemia and at 1, 7, 14, and 30 days post-perfusion (n = 10 at each time point). Similarly, GAP-43 and neurocan expression was detected in the right hemisphere of naive and sham-operated animals. The results were expressed as positive cells. RESULTS: A total of 100 rats were included in the final analysis. The number of GAP-43 positive cells increased in the CVB-D group 1, 7, 14, and 30 days post-cerebral ischemia/perfusion compared to the lesion group, as indicated by a significant difference between the CVB-D and lesion group (P 〈 0.054).01). The number of neurocan-positive cells decreased in the CVB-D group on the first day compared to the model group; however, there was no significant difference between the two groups (P 〉 0.05). On post-ischemia days 7, 14, and 30, the number of neurocan-positive cells in the CVB-D group was significantly less than in the lesion group (P 〈 0.05). Both, GAP-43 and neurocan expression was not detectable in brains of naive and sham-operated animals. CONCLUSION: CVB-D treatment up-regulated GAP-43 expression and down-regulated neurocan expression in the ischemic region of RHRSP rats. 展开更多
关键词 cerebral ischemia/perfusion human growth-associated protein 43 NEUROCAN cyclovirobuxine D rats
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数字普惠金融对地区金融韧性提升的影响——基于283个城市面板数据的实证检验 被引量:2
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作者 林春 张鑫 孙英杰 《经济学报》 2025年第2期135-153,共19页
数字普惠金融是新发展阶段下提升地区金融韧性的重要引擎。基于此,本文以数字普惠金融为切入点,采用2011—2019年283个城市的面板数据,探讨数字普惠金融对我国地区金融韧性的影响。结果表明:数字普惠金融对地区金融韧性具有显著的提升作... 数字普惠金融是新发展阶段下提升地区金融韧性的重要引擎。基于此,本文以数字普惠金融为切入点,采用2011—2019年283个城市的面板数据,探讨数字普惠金融对我国地区金融韧性的影响。结果表明:数字普惠金融对地区金融韧性具有显著的提升作用,教育水平和消费水平是二者间重要的传导机制,且创新创业水平的提高有利于该作用的有效发挥。同时,该作用在数字普惠金融子维度、分业务、地理区位、传统金融发展及对外开放水平方面表现出显著的异质性特征。此外,数字普惠金融对地区金融韧性的影响存在一定的非线性关系,即呈现倒U型结构。本文结论既为深入理解数字普惠金融对我国金融发展的影响提供了新视角,又为新时代下加快金融强国建设指明了方向。 展开更多
关键词 数字普惠金融 金融韧性 教育水平 消费水平 创新创业水平
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机器学习辅助减反膜结构设计与界面修饰协同优化的高效稳定钙钛矿太阳能电池
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作者 梁英 邓羽恒 +13 位作者 余士律 程家豪 宋嘉伟 姚俊 杨亦辰 张万雷 周文靖 张欣 沈文剑 梁桂杰 李彬 彭勇 胡润 李望南 《物理化学学报》 北大核心 2025年第9期73-82,共10页
近年来,单节钙钛矿太阳电池(PSCs)通过对功能层进行多元优化策略最小化能量损失使器件效率迅速提升,逐渐逼近肖克利-奎伊瑟(S-Q)理论效率极限。作为光管理策略的重要组成部分,减反射涂层(ARC)在降低光学能量损耗实现高效率方面发挥着关... 近年来,单节钙钛矿太阳电池(PSCs)通过对功能层进行多元优化策略最小化能量损失使器件效率迅速提升,逐渐逼近肖克利-奎伊瑟(S-Q)理论效率极限。作为光管理策略的重要组成部分,减反射涂层(ARC)在降低光学能量损耗实现高效率方面发挥着关键作用。开发出具有多功能的ARC,能够同时提升可见光透过率、抑制紫外光(UV)透射,并且在玻璃基底上具有优异附着性、耐磨性是目前研发的重点。本研究利用贝叶斯优化算法的机器学习方法指导超薄多层二氧化物ARC的结构设计。优化流程包括多层氧化物薄膜的参数化建模、采用传递矩阵法(TMM)的物理模拟,以及抗反射性能评估。经过优化的ARC采用100 nm SiO_(2)-10 nm TiO_(2)-10 nm SiO_(2)(STS)叠层结构,使导电玻璃基底在400–800 nm范围内的透光率提升了9.2%。该结构应用在PSCs中获得了最高96.94%的外量子效率,使短路电流密度和光电转换效率均提升了4%,紫外光照持续300 h后仍保持有初始效率的81.2%,而标样组的效率降至~69%,表明STS ARC具备有效的紫外光过滤性能。STS ARC经过国际标准测试具有超过9H的硬度和ISO 0级以及ASTM 5B级附着度,满足太阳电池户外应用需求。除光学能量损失外,钙钛矿表面缺陷态富集导致非辐射复合能量损失,同时也是晶格降解的起始位点。因此,本文采用3-脒基吡啶氢碘酸盐(3-PyADI)对界面缺陷进行钝化修饰,协同将PSCs的效率提升至24.44%,未封装的器件在大气环境下放置1000 h后保留初始效率的93%。本研究所提出的增透减反薄膜与钙钛矿界面修饰协同实现器件性能和稳定性的同步提升,为钙钛矿太阳电池的产业化发展探索出具有前景且实用的路径。 展开更多
关键词 机器学习 减反膜 光管理策略 钙钛矿太阳电池 界面修饰
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Investigating the Relationship between Age-Related Cardiac Hypertrophy, Skeletal Muscle Strength, and the FNDC5 Protein as a Potential Regulator
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作者 Tao Feng Ziyang Fang +9 位作者 Yinjun Luo xin zhang Ying Li Shijing Ma Jinting Wei Xiaoyan Fang Biao Li Lingling Huang Jinhua Wang Suchan Liao 《Journal of Biosciences and Medicines》 2025年第2期450-464,共15页
Background: Aging-induced cardiac hypertrophy and reduced skeletal muscle strength contribute to increased disease risk and life burden in the elderly. FNDC5 acts as a protective muscle factor in both cardiac and skel... Background: Aging-induced cardiac hypertrophy and reduced skeletal muscle strength contribute to increased disease risk and life burden in the elderly. FNDC5 acts as a protective muscle factor in both cardiac and skeletal muscle. This study aims to examine the relationship between cardiac FNDC5 and aging-related cardiac hypertrophy and decreased skeletal muscle strength. Methods: Male young C57BL/6 mice (5 months old, n = 6) and aged mice (21 months old, n = 6) were utilized in the study and housed in a specific pathogen-free (SPF) environment. Prior to the experiment, grip strength tests were performed on the mice, and heart tissues were collected for morphological analysis, including the assessment of peroxisome proliferator-activated receptor gamma coactivator 1α (PGC-1α) and fibronectin type III-containing structural domain 5 (FNDC5) protein levels. Furthermore, myosin heavy chain II (MyHC II), skeletal muscle-specific transcription factor (MyoD), muscle RING-finger protein-1 (MuRF1), and FNDC5 levels were evaluated in the quadriceps muscle. The correlations between heart weight and FNDC5 expression levels, as well as skeletal muscle indices in the mice, were subsequently analyzed. Result: Aging leads to cardiac hypertrophy and reduced expression of PGC-1α and FNDC5 proteins. Concurrently, there is a decline in the strength of skeletal muscle, along with decreased expression of MyHC II and increased expression of MURF1 and MyoD. Correlation analysis demonstrated strong positive associations between myocardial FNDC5 protein levels and limb grip strength, as well as MyHC II, and strong negative associations with MyoD and MuRF1. Conclusion: There may be a significant association between aging-induced cardiac hypertrophy and decreased skeletal muscle strength, with FNDC5 potentially playing a crucial role as a regulatory molecule facilitating communication between the heart and skeletal muscle. 展开更多
关键词 AGING Heart Hypertrophy Skeletal Muscle FNDC5
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具备卷曲结构的聚偏二氟乙烯/二氧化钛纤维膜的制备与空气过滤性能
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作者 克力木·吐鲁干 张鑫 +2 位作者 赵伟 李翔 田鹏 《高分子材料科学与工程》 北大核心 2025年第5期58-67,共10页
文中通过静电纺丝技术制备了不同纳米二氧化钛(TiO_(2))颗粒掺入量的卷曲结构聚偏二氟乙烯(PVDF)/TiO_(2)纳米纤维膜,探讨了其在空气过滤中的应用性能。通过调整纺丝过程中的相对湿度,成功制得了具有三维卷曲外观的纳米纤维。还探讨了Ti... 文中通过静电纺丝技术制备了不同纳米二氧化钛(TiO_(2))颗粒掺入量的卷曲结构聚偏二氟乙烯(PVDF)/TiO_(2)纳米纤维膜,探讨了其在空气过滤中的应用性能。通过调整纺丝过程中的相对湿度,成功制得了具有三维卷曲外观的纳米纤维。还探讨了TiO_(2)颗粒加入量对纤维膜微观结构、静电特性及其过滤性能的影响。研究发现,适当增加纳米TiO_(2)的比例能够有效增强纤维膜的静电吸附能力,特别是在过滤直径为0.3μm的氯化钠气溶胶颗粒方面,显示出了卓越的拦截能力。掺入0.5%的纳米二氧化钛驻极增强剂时,卷曲结构PVDF/TiO_(2)纤维膜的纤维均匀,过滤效率最高达到99.995%,阻力压降为49.83 Pa,品质因子0.096。提升纤维膜克重后,过滤效率提升到国家标准KN100级别,高湿度环境中模拟实际使用8 h后,过滤效率仍能达到99.918%的水平,压阻约为60 Pa,对纤维膜进行长时间(30 d)过滤效率检测,过滤效率完全满足99.5%以上的水平。为设计和制备高效、低阻力的空气过滤材料提供了重要的理论依据和实践指导。 展开更多
关键词 静电纺丝 卷曲结构 复合材料 空气过滤 纳米纤维
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雪宝顶流域黄龙彩池新生钙华生物沉积特性 被引量:2
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作者 董鹏举 李琼芳 +8 位作者 董发勤 代群威 刘凡 宋娜 赵晓夏 崔杰 罗尧东 xin zhang O’Driscoll Mike 《中国岩溶》 CAS CSCD 北大核心 2021年第1期88-98,共11页
为探究钙华沉积的生物特性,以雪宝顶流域黄龙景区的五彩池和争艳彩池为研究对象,采集和分析研究点藻类的优势种类,利用傅里叶变换红外光谱仪和高效液相色谱确定优势藻胞外产物的主要组成和含量,并采用X射线荧光光谱仪、X射线衍射光谱仪... 为探究钙华沉积的生物特性,以雪宝顶流域黄龙景区的五彩池和争艳彩池为研究对象,采集和分析研究点藻类的优势种类,利用傅里叶变换红外光谱仪和高效液相色谱确定优势藻胞外产物的主要组成和含量,并采用X射线荧光光谱仪、X射线衍射光谱仪、傅里叶变换红外光谱仪和扫描电子显微镜分析其新生钙华的元素组成、物相结构和微观形貌。结果表明:五彩池和争艳彩池的优势藻类分别是黄藻门(Xanthophyceae)和硅藻门(Bacillariophyta),藻类的胞外产物主要为蛋白质、多糖和有机酸;新生钙华以方解石为主,表面含羧基、甲基、醛基等基团;与无藻类参与的钙华沉积物对比,新生钙华晶体无特定形状,并出现溶蚀及穿孔现象。藻类及其胞外产物参与钙华沉积过程,调控钙华晶体微观形貌。 展开更多
关键词 新生钙华 生物沉积 藻类 晶体形貌
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暗场显微镜下的纳米颗粒识别与观测细胞膜上的扩散运动——推荐一个化学测量学实验
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作者 孙元芳 张然 +4 位作者 罗天 张欣 王翊如 黄腾翔 方宁 《大学化学》 2025年第2期121-129,共9页
单颗粒示踪是实现动态生物过程实时观测的重要技术突破,对于挖掘静态观察中所隐藏的机制尤为重要。随着光学显微成像的发展,商品化仪器能够轻松实现微观尺度下对于生物过程的实时观察。本实验采用纳米金、银材料作为成像探针,探讨了等... 单颗粒示踪是实现动态生物过程实时观测的重要技术突破,对于挖掘静态观察中所隐藏的机制尤为重要。随着光学显微成像的发展,商品化仪器能够轻松实现微观尺度下对于生物过程的实时观察。本实验采用纳米金、银材料作为成像探针,探讨了等离激元纳米材料的尺寸效应;并设计活细胞成像实验,通过观察金纳米棒在细胞膜上的扩散运动将单颗粒示踪技术引入本科生教学,并将其作为化学测量学的示范性试验。本实验内容丰富、趣味性强,面向已基本掌握化学、化学生物学等基础知识并对化学测量学感兴趣的二、三年级本科生,旨在将单颗粒示踪领域研究前沿融入本科生教学,引导学生自主探索,有利于激发学生的科研兴趣与培养专业素养。 展开更多
关键词 单颗粒示踪 等离激元纳米颗粒 活细胞成像 科教融合 综合化学实验
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热力学基本方程相关公式倒“∏”图形记忆法及教学实践
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作者 王枫梅 张欣 +2 位作者 鄢红 徐向宇 王桂荣 《大学化学》 2025年第11期369-375,共7页
在物理化学课程学习的过程中,如何高效准确地理解并总结化学热力学公式是学生所面临的主要难题。一方面体现在学生对公式理解不够深入,另一方面是热力学理论体系复杂,八个状态函数之间的关系容易混淆。本文旨在探讨涉及热力学中八个状... 在物理化学课程学习的过程中,如何高效准确地理解并总结化学热力学公式是学生所面临的主要难题。一方面体现在学生对公式理解不够深入,另一方面是热力学理论体系复杂,八个状态函数之间的关系容易混淆。本文旨在探讨涉及热力学中八个状态方程之间的关系式,及快速记忆掌握方法。内容包括探讨热力学基本方程、对应系数关系式,及麦克斯韦关系式的记忆方法和利用动画视频协助记忆。通过引入新的教学策略和记忆方法,帮助学生更好地理解和掌握这些公式,提高学习效果并打好热力学基础。 展开更多
关键词 物理化学 热力学基本方程 倒“∏”图形记忆法 麦克斯韦关系式
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雪宝顶流域黄龙“8·8”地震后短期内主 要水环境变化特征 被引量:1
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作者 赵晓夏 李琼芳 +8 位作者 董发勤 代群威 宋娜 董鹏举 崔杰 罗尧东 张强 xin zhang O’Driscoll Mike 《中国岩溶》 CAS CSCD 北大核心 2021年第1期77-87,共11页
富含Ca^(2+)和HCO^(-)_(3)的水体是黄龙钙华地貌得以持续沉积的首要条件。为明确2017年九寨沟“8∙8”地震是否对黄龙脆弱钙华体产生影响并进而导致水环境的改变,于2017年10月和2018年8月对黄龙3个主要监测点进行了水样采集和水质参数检... 富含Ca^(2+)和HCO^(-)_(3)的水体是黄龙钙华地貌得以持续沉积的首要条件。为明确2017年九寨沟“8∙8”地震是否对黄龙脆弱钙华体产生影响并进而导致水环境的改变,于2017年10月和2018年8月对黄龙3个主要监测点进行了水样采集和水质参数检测。通过主成分分析震前的多次水质检测结果,得到影响黄龙水化学的主要参数,并与震后的水化学参数进行对比分析,发现:2016年(震前)水质参数显示pH、总磷、总氮对黄龙水质起主要贡献作用,地震后水体的pH、Ca^(2+)和HCO^(-)_(3)含量上升,而总磷含量则下降较多,表明地震对黄龙钙华体内部结构产生了影响,导致上升泉(转花泉)中的Ca^(2+)和HCO^(-)_(3)含量增加,并影响了pH,而震后水体中的总磷含量减少,这可能与游客数量大幅度减少有关;“8∙8”地震对黄龙钙华沉积区水环境造成了影响,并有利于钙华沉积。 展开更多
关键词 钙华 地震 水化学 黄龙
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综合化学实验设计:非稠环电子受体的设计、合成及光电性质研究
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作者 刘文旭 韩峰 +4 位作者 王博轩 刘骅驿 古晓斌 张昕 刘瑶 《大学化学》 2025年第10期263-275,共13页
本文设计了一个以非稠环电子受体材料为核心的综合实验,涵盖分子合成及光电性质研究。实验创新性地将太阳能利用与Suzuki偶联反应引入教学,通过“文献研读-实验操作-机理探讨”模式深化“结构决定性质”的化学思维。培养学生实验操作及... 本文设计了一个以非稠环电子受体材料为核心的综合实验,涵盖分子合成及光电性质研究。实验创新性地将太阳能利用与Suzuki偶联反应引入教学,通过“文献研读-实验操作-机理探讨”模式深化“结构决定性质”的化学思维。培养学生实验操作及数据处理能力,同时融入绿色化学理念,有效提升学生的创新意识与协作能力,为科研深造奠定基础。 展开更多
关键词 综合化学实验 电子受体 光电性质 绿色化学观
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All-optical nonlinear activation functions realized on phasechange photonic integrated circuits with microheaters 被引量:3
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作者 Jiyuan Jiang Bingxin Ding +8 位作者 Shiyu Li xin zhang Haihua Wang Jie Wu Xiaoyan Liu Zhou Wang Xiaojuan Lian Wen Huang Lei Wang 《Journal of Semiconductors》 2025年第2期122-131,共10页
Photonic neural networks have garnered significant attention in recent years due to their ultra-high computational speed,broad bandwidth,and parallel processing capabilities.However,compared to conventional electronic... Photonic neural networks have garnered significant attention in recent years due to their ultra-high computational speed,broad bandwidth,and parallel processing capabilities.However,compared to conventional electronic nonlinear activa-tion function(NAF),progress on efficient and easily implementable optical nonlinear activation function(ONAF)was barely reported.To address this issue,we proposed a programmable,low-loss ONAF device based on a silicon micro-ring resonator capped with the Antimony selenide(Sb_(2)Se_(3))thin films,and with indium tin oxide(ITO)used as the microheater.Leveraging our self-developed phase-transformation kinetic and optical models,we successfully simulated the phase-transition behavior of Sb_(2)Se_(3)and three different ONAFs—ELU,ReLU,and radial basis function(RBF)were achieved according to discernible optical responses of proposed devices under different phase-change extents.Classification results from the Fashion MNIST dataset demonstrated that these ONAFs can be considered as appropriate substitutes for traditional NAF.This indicated the bright prospect of the proposed device for nonlinear activation function in future photonic neural networks. 展开更多
关键词 ONAF Sb_(2)Se_(3) MICROHEATER photonic neural networks
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Porous sorbents for direct capture of carbon dioxide from ambient air 被引量:2
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作者 Yuchen zhang Lifeng Ding +3 位作者 Zhenghe Xie xin zhang Xiaofeng Sui Jian-Rong Li 《Chinese Chemical Letters》 2025年第3期125-133,共9页
Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given... Large-scale deployment of carbon dioxide(CO_(2))removal technology is an essential step to cope with global warming and achieve carbon neutrality.Direct air capture(DAC)has recently received increasing attention given the high flexibility to remove CO_(2)from discrete sources.Porous materials with adjustable pore characteristics are promising sorbents with low or no latent heat of vaporization.This review article has summarized the recent development of porous sorbents for DAC,with a focus of pore engineering strategy and adsorption mechanism.Physisorbents such as zeolites,porous carbons,metal-organic frameworks(MOFs),and amine-modified chemisorbents have been discussed and their challenges in practical application have been analyzed.At last,future directions have been proposed,and it is expected to inspire collaborations from chemistry,environment,material science and engineering communities. 展开更多
关键词 Direct air capture Carbon neutrality Porous materials PHYSISORPTION CHEMISORPTION
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Effects of discrete fracture networks on simulating hydraulic fracturing,induced seismicity and trending transition of relative modulus in coal seams 被引量:1
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作者 xin zhang Guangyao Si +3 位作者 Qingsheng Bai Joung Oh Biao Jiao Wu Cai 《International Journal of Coal Science & Technology》 2025年第1期263-278,共16页
Discrete fracture network(DFN)commonly existing in natural rock masses plays an important role in geological complexity which can influence rock fracturing behaviour during fluid injection.This paper simulated the hyd... Discrete fracture network(DFN)commonly existing in natural rock masses plays an important role in geological complexity which can influence rock fracturing behaviour during fluid injection.This paper simulated the hydraulic fracturing process in lab-scale coal samples with DFNs and the induced seismic activities by the discrete element method(DEM).The effects of DFNs on hydraulic fracturing,induced seismicity and elastic property changes have been concluded.Denser DFNs can comprehensively decrease the peak injection pressure and injection duration.The proportion of strong seismic events increases first and then decreases with increasing DFN density.In addition,the relative modulus of the rock mass is derived innovatively from breakdown pressure,breakdown fracture length and the related initiation time.Increasing DFN densities among large(35–60 degrees)and small(0–30 degrees)fracture dip angles show opposite evolution trends in relative modulus.The transitional point(dip angle)for the opposite trends is also proportionally affected by the friction angle of the rock mass.The modelling results have much practical meaning to infer the density and geometry of pre-existing fractures and the elastic property of rock mass in the field,simply based on the hydraulic fracturing and induced seismicity monitoring data. 展开更多
关键词 Discrete fracture network Hydraulic fracturing Discrete element method Induced seismicity Relative modulus
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Wear behavior of functionally graded cemented carbides with CoNiFeCr multi-principal-element alloy binder 被引量:1
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作者 Cheng Qian Kun Li +5 位作者 Yong Liu xin zhang Shuailong zhang Ji zhang Lijun Jiang Huichao Cheng 《Journal of Materials Science & Technology》 2025年第14期245-267,共23页
The good combination of mechanical and wear properties for cemented carbides is crucial.In this work,the wear behavior of functionally graded cemented carbide(FGCC)and non-graded cemented carbide(CC),with CoNiFeCr mul... The good combination of mechanical and wear properties for cemented carbides is crucial.In this work,the wear behavior of functionally graded cemented carbide(FGCC)and non-graded cemented carbide(CC),with CoNiFeCr multi-principal-element alloy(MPEA)binder,has been investigated by performing sliding wear tests and composition characterization.The results showed that compared with CC,FGCC had higher hardness,stronger fracture toughness,better wear performance,and similar TRS.FGCCs exhibited lower wear rates(3.44×10^(−7)–6.95×10^(−6)mm^(3)/(N m))and coefficients of friction(COFs)(0.27–0.39)than CCs from RT to 600℃due to mitigation of multiple risks caused by binder removal,fragmentation and pull-out of WC grains,high-temperature oxidation and softening.In the low-temperature wear stage,the MPEA binder underwent dynamic recrystallization(DRX)and twinning deformation before removing from the surface.The binder removal caused dislocation pile-ups and stacking faults(SFs)to form under high stress,resulting in fragmentation and pull-out of WC grains.The low-temperature wear was dominated by abrasive wear and adhesive wear,with a low wear rate and a high and unstable COF.In the high-temperature wear stage,initial pitting oxidation of WC grains generated many subgrain boundaries,reducing heat transfer and exacerbating oxidation,resulting in an oxide layer enriched with WO3,Mx Oy,and MWO4.High-temperature wear was dominated by oxidation wear and high-temperature softening,with a high wear rate and a low and smooth COF.The results from the present study do not only provide theoretical guidance for an understanding of the antiwear mechanism of WC-CoNiFeCr,but also a new approach for the preparation of cemented carbides with high wear resistance. 展开更多
关键词 Wear behavior Graded cemented carbide Non-graded cemented carbide Multi-principal-element alloy Sliding wear tests
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基于双ABC-X模型的中青年冠心病患者PCI术后早期重返工作自我效能现状及影响因素分析
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作者 蔡晓雪 王建辉 +2 位作者 张培枝 张鑫 赵薇 《医学研究前沿》 2025年第11期22-27,共6页
目的基于双ABC-X模型调查中青年冠心病患者PCI术后早期重返工作自我效能现状及影响因素分析,为制定针对性的家庭护理干预提供理论依据。方法采用患者一般资料问卷、重返工作岗位自我效能问卷、疾病进展恐惧量表、慢性病健康素养量表对36... 目的基于双ABC-X模型调查中青年冠心病患者PCI术后早期重返工作自我效能现状及影响因素分析,为制定针对性的家庭护理干预提供理论依据。方法采用患者一般资料问卷、重返工作岗位自我效能问卷、疾病进展恐惧量表、慢性病健康素养量表对363例PCI术后患者进行调查,采用配偶一般资料问卷和返岗期望问卷对配偶进行调查。结果中青年冠心病患者PCI术后早期重返工作自我效能得分(3.73±1.52)分;多元线性回归分析结果显示,患者的疾病进展恐惧、健康素养及配偶的冠心病知识了解程度和返岗期望是中青年冠心病患者PCI术后早期重返工作自我效能的影响因素(均P<0.05),可解释总变异的60.7%。结论中青年冠心病患者PCI术后早期重返工作自我效能处于较低水平,医护人员应重视对患者重返工作自我效能的评估,以家庭为单位进行疾病知识和返岗相关教育,减少患者及配偶对疾病的担忧,缩短病假时间,提高返岗率。 展开更多
关键词 中青年 PCI 重返工作自我效能 配偶 影响因素
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The cGAS−STING-mediated ROS and ferroptosis are involved in manganese neurotoxicity 被引量:1
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作者 Zhimin zhang Jirui Yang +5 位作者 Qiongli Zhou Shiyin Zhong Jingjing Liu xin zhang Xuhong Chang Hui Wang 《Journal of Environmental Sciences》 2025年第6期71-86,共16页
Manganese(Mn)has been characterized as an environmental pollutant.Excessive releases of Mn due to human activities have increased Mn levels in the environment over the years,posing a threat to human health and the env... Manganese(Mn)has been characterized as an environmental pollutant.Excessive releases of Mn due to human activities have increased Mn levels in the environment over the years,posing a threat to human health and the environment.Long-term exposure to high concentrations of Mn can induce neurotoxicity.Therefore,toxicological studies on Mn are of paramount importance.Mn induces oxidative stress through affecting the level of reactive oxygen species(ROS),and the overabundance of ROS further triggers ferroptosis.Additionally,Mn^(2+) was found to be a novel activator of the cyclic guanosine-adenosine synthase(cGAS)−stimulator of interferon genes(STING)pathway in the innateimmune system.Thus,we speculate thatMn exposuremay promote ROS production by activating the cGAS−STING pathway,which further induces oxidative stress and ferroptosis,and ultimately triggers Mn neurotoxicity.This review discusses the mechanism between Mn-induced oxidative stress and ferroptosis via activation of the cGAS−STING pathway,which may offer a prospective direction for future in-depth studies on the mechanism of Mn neurotoxicity. 展开更多
关键词 cGAS−STING pathway Ferroptosis Oxidative stress NEUROTOXICITY MANGANESE
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EILnet: An intelligent model for the segmentation of multiple fracture types in karst carbonate reservoirs using electrical image logs 被引量:1
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作者 Zhuolin Li Guoyin zhang +4 位作者 Xiangbo zhang xin zhang Yuchen Long Yanan Sun Chengyan Lin 《Natural Gas Industry B》 2025年第2期158-173,共16页
Karst fractures serve as crucial seepage channels and storage spaces for carbonate natural gas reservoirs,and electrical image logs are vital data for visualizing and characterizing such fractures.However,the conventi... Karst fractures serve as crucial seepage channels and storage spaces for carbonate natural gas reservoirs,and electrical image logs are vital data for visualizing and characterizing such fractures.However,the conventional approach of identifying fractures using electrical image logs predominantly relies on manual processes that are not only time-consuming but also highly subjective.In addition,the heterogeneity and strong dissolution tendency of karst carbonate reservoirs lead to complexity and variety in fracture geometry,which makes it difficult to accurately identify fractures.In this paper,the electrical image logs network(EILnet)da deep-learning-based intelligent semantic segmentation model with a selective attention mechanism and selective feature fusion moduledwas created to enable the intelligent identification and segmentation of different types of fractures through electrical logging images.Data from electrical image logs representing structural and induced fractures were first selected using the sliding window technique before image inpainting and data augmentation were implemented for these images to improve the generalizability of the model.Various image-processing tools,including the bilateral filter,Laplace operator,and Gaussian low-pass filter,were also applied to the electrical logging images to generate a multi-attribute dataset to help the model learn the semantic features of the fractures.The results demonstrated that the EILnet model outperforms mainstream deep-learning semantic segmentation models,such as Fully Convolutional Networks(FCN-8s),U-Net,and SegNet,for both the single-channel dataset and the multi-attribute dataset.The EILnet provided significant advantages for the single-channel dataset,and its mean intersection over union(MIoU)and pixel accuracy(PA)were 81.32%and 89.37%,respectively.In the case of the multi-attribute dataset,the identification capability of all models improved to varying degrees,with the EILnet achieving the highest MIoU and PA of 83.43%and 91.11%,respectively.Further,applying the EILnet model to various blind wells demonstrated its ability to provide reliable fracture identification,thereby indicating its promising potential applications. 展开更多
关键词 Karst fracture identification Deep learning Semantic segmentation Electrical image logs Image processing
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