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(B_(4)C+Al_(2)O_(3))/Al中子吸收材料的稳定化工艺
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作者 石宝铭 昝宇宁 +2 位作者 王全兆 肖伯律 马宗义 《科技导报》 北大核心 2026年第2期98-107,共10页
(B_(4)C+Al_(2)O_(3))/Al复合材料作为乏燃料干式贮存系统中的关键中子吸收材料,其在高温下长期服役的可靠性直接关系到核废料安全管理的有效性。该结构功能一体化材料在高温下存在非晶Al_(2)O_(3)(am-Al_(2)O_(3))向γ-Al_(2)O_(3)相... (B_(4)C+Al_(2)O_(3))/Al复合材料作为乏燃料干式贮存系统中的关键中子吸收材料,其在高温下长期服役的可靠性直接关系到核废料安全管理的有效性。该结构功能一体化材料在高温下存在非晶Al_(2)O_(3)(am-Al_(2)O_(3))向γ-Al_(2)O_(3)相变的风险,可能导致力学性能降低,但目前对其组织演化规律及性能稳定性的认识仍不足。为此,对(B_(4)C+Al_(2)O_(3))/Al复合材料进行了400℃/100 h和550℃/8 h 2种稳定化工艺处理,并通过400℃下最长4000 h的退火实验验证其长期稳定性。结果表明,经稳定化处理后,复合材料在室温及350℃下的抗拉强度分别保持在220.0和100.0 MPa以上,满足工程应用需求。微观组织分析表明,am-Al_(2)O_(3)部分转化为γ-Al_(2)O_(3),但材料在退火过程中组织与性能均趋于稳定。2种工艺均能有效提升材料的热稳定性,为(B_(4)C+Al_(2)O_(3))/Al复合材料制备的乏燃料干式贮存容器实现长期安全服役提供了材料学依据。 展开更多
关键词 中子吸收材料 (B_(4)c+Al_(2)O_(3))/Al复合材料 稳定化工艺 力学性能 微观组织
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N掺杂TiO_(2)-Fe_(2)O_(3)/C光催化剂的制备及其光催化降解性研究 被引量:2
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作者 李洁 张佳 +1 位作者 陈连喜 吕博 《化工新型材料》 北大核心 2025年第2期210-214,共5页
为寻找一种简便且具有良好孔结构的光催化剂合成路径,提升并拓宽其光催化应用范围,通过将N掺杂的双金属Ti-Fe MOFs在500℃的空气气氛中直接热解制备N掺杂TiO_(2)-Fe_(2)O_(3)/C纳米结构。获得的产物显示出独特的树枝状结构,且具有较大... 为寻找一种简便且具有良好孔结构的光催化剂合成路径,提升并拓宽其光催化应用范围,通过将N掺杂的双金属Ti-Fe MOFs在500℃的空气气氛中直接热解制备N掺杂TiO_(2)-Fe_(2)O_(3)/C纳米结构。获得的产物显示出独特的树枝状结构,且具有较大比表面积和良好的介孔结构。同时,红外光谱(FT-IR)和X射线光电子能谱(XPS)结果证实,在空气条件下煅烧后,衍生物仍保留了N和C成分。此外,将制备的N掺杂树枝状双金属结构多孔材料作为光催化剂用于降解亚甲基蓝(MB)染料。结果表明:N掺杂TiO_(2)-Fe_(2)O_(3)/C比N掺杂非Fe参与的TiO_(2)/C和非N非Fe掺杂TiO_(2)/C具有更好的光催化性能,且N掺杂TiO_(2)-Fe_(2)O_(3)/C对MB染料的有效降解率达到81%。 展开更多
关键词 Ti基-MOFs Fe基-MOFs tio_(2)-Fe_(2)O_(3)/c N掺杂 光催化
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C3H10T1/2细胞分化为成熟棕色脂肪细胞的培养、诱导分化及鉴定
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作者 冯晴晴 陈思沅 +8 位作者 潘静芸 王瑞婷 张纸麟 曾莹 廖俊斌 陈锦贤 陈赣英 林丹蓉 朱伟 《中国病理生理杂志》 北大核心 2026年第2期409-416,共8页
目的:通过对C3H10T1/2细胞分化为成熟棕色脂肪细胞的培养、诱导分化及鉴定,深入探讨棕色脂肪细胞的生物学特性,为人类棕色脂肪细胞的相关研究提供实验参考与理论依据。方法:C3H10T1/2细胞经细胞接种、培养及诱导分化处理,利用光学显微... 目的:通过对C3H10T1/2细胞分化为成熟棕色脂肪细胞的培养、诱导分化及鉴定,深入探讨棕色脂肪细胞的生物学特性,为人类棕色脂肪细胞的相关研究提供实验参考与理论依据。方法:C3H10T1/2细胞经细胞接种、培养及诱导分化处理,利用光学显微镜观察细胞形态变化,并通过油红O染色、免疫荧光法、线粒体探针法以及线粒体电镜技术对分化细胞进行鉴定分析。结果:未分化的C3H10T1/2细胞形态多样,具有突触伸展特征;分化后的细胞逐渐变为圆形或椭圆形,形成环形脂滴;未分化组细胞形态无明显变化。油红O染色显示,未分化组细胞基本无染色,而分化组中约90%的细胞红染,脂滴分布于细胞核周围,吸光度值显著升高(P<0.05)。分化组解偶联蛋白1(uncoupling protein 1,UCP1)、过氧化物酶体增殖激活受体γ(peroxisome proliferator-activated receptorγ,PPARγ)辅激活因子1α(PPARγco-activator-1α,PGC-1α)、PPARγ和转录因子PRDM16的相对荧光强度和蛋白表达量显著高于未分化组(P<0.05),且线粒体活性增强。结论:本研究成功诱导C3H10T1/2细胞分化为成熟棕色脂肪细胞,结合细胞形态观察、关键蛋白表达检测及线粒体功能分析进行综合评估,证实了细胞的有效分化及成熟棕色脂肪细胞的功能特性。 展开更多
关键词 c3H10T1/2细胞 棕色脂肪细胞 细胞培养 细胞分化 鉴定
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自发性乳糜疾病患者PROX1、FOXC2和VEGFR3基因表达模式的研究
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作者 俞家顺 夏维木 +8 位作者 唐崎 李文敏 郑勇军 郑立传 于澎 李展翅 叶惟靖 吕向国 周燕峰 《转化医学杂志》 2026年第1期25-29,共5页
目的探讨淋巴管发育关键基因群前同源盒基因1(PROX1)、叉头框蛋白C2(FOXC2)和血管内皮生长因子受体3(VEGFR3)与自发性乳糜疾病的相关性。方法回顾性选取2019年1月至2023年12月上海市浦东新区浦南医院收治的25例自发性乳糜疾病患者为患者... 目的探讨淋巴管发育关键基因群前同源盒基因1(PROX1)、叉头框蛋白C2(FOXC2)和血管内皮生长因子受体3(VEGFR3)与自发性乳糜疾病的相关性。方法回顾性选取2019年1月至2023年12月上海市浦东新区浦南医院收治的25例自发性乳糜疾病患者为患者组,另选取同期体检的20例健康志愿者为对照组,比较两组受试者PROX1、FOXC2、VEGFR3蛋白及基因表达水平。结果25例自发性乳糜疾病患者中,乳糜尿11例,乳糜腹6例,乳糜胸8例。患者组与对照组PROX1、FOXC2及VEGFR3全血蛋白表达水平比较,差异无统计学意义(P>0.05);患者组PROX1、FOXC2及VEGFR3的mRNA表达水平均高于对照组(P<0.05),乳糜尿、乳糜胸、乳糜腹患者PROX1和FOXC2表达水平比较,差异均无统计学意义(P>0.05)。结论PROX1、FOXC2及VEGFR3基因在自发性乳糜疾病中表达上调,提示这些基因可能通过影响淋巴管结构和功能参与疾病的发生和发展。 展开更多
关键词 自发性乳糜疾病 淋巴管病变 前同源盒基因1 叉头框蛋白c2 血管内皮生长因子受体3 基因表达
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C掺Sb_(2)Te_(3)相变薄膜在柔性衬底PI上的性能研究
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作者 潘晨杰 高士伟 吴良才 《东华大学学报(自然科学版)》 北大核心 2026年第1期105-111,共7页
相变存储器(PCM)是一种极具发展前景的柔性电子存储技术,但传统PCM的研究大多基于刚性衬底,无法满足柔性化的需求。选择在柔性衬底聚酰亚胺(PI)上制备了碳(C)掺杂Sb_(2)Te_(3)(C-Sb_(2)Te_(3)/PI)相变薄膜及器件单元,并研究了弯曲对薄... 相变存储器(PCM)是一种极具发展前景的柔性电子存储技术,但传统PCM的研究大多基于刚性衬底,无法满足柔性化的需求。选择在柔性衬底聚酰亚胺(PI)上制备了碳(C)掺杂Sb_(2)Te_(3)(C-Sb_(2)Te_(3)/PI)相变薄膜及器件单元,并研究了弯曲对薄膜相变性能的影响。结果表明,C-Sb_(2)Te_(3)/PI薄膜在未弯曲及弯曲1000、5000和10000次后仍能完成相变过程且高低阻值稳定,具有良好的抗弯曲性能。多次弯曲未对薄膜的晶体结构和微观形貌产生影响。使用光刻工艺制备的C-Sb_(2)Te_(3)器件单元具有较快的相变速度(10 ns)和良好的循环特性(10~3次左右)。因此,C-Sb_(2)Te_(3)/PI在柔性存储器领域表现出应用潜力。 展开更多
关键词 c掺Sb_(2)Te_(3) PI 柔性电子存储技术 抗弯曲 循环特性
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高纯炭黑对Al_(2)O_(3)-SiC-C质铁沟浇注料性能的影响
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作者 王成春 阳方 +2 位作者 张弛 周辉 刘威 《耐火与石灰》 2026年第1期16-19,28,共5页
为了减少铁沟料中沥青的使用对人体健康和环境产生的危害,采用电熔低碳棕刚玉、电熔白刚玉、碳化硅、球状沥青、铝酸盐水泥、煅烧活性氧化铝微粉为主要原料,加入0、0.5%(w)、1%(w)、1.5%(w)、2%(w)高纯炭黑替代等量的球状沥青,制备了出... 为了减少铁沟料中沥青的使用对人体健康和环境产生的危害,采用电熔低碳棕刚玉、电熔白刚玉、碳化硅、球状沥青、铝酸盐水泥、煅烧活性氧化铝微粉为主要原料,加入0、0.5%(w)、1%(w)、1.5%(w)、2%(w)高纯炭黑替代等量的球状沥青,制备了出铁沟用Al_(2)O_(3)-SiC-C质浇注料,研究了炭黑加入量对浇注料体积密度、强度、抗氧化性能、抗侵蚀性能的影响。结果表明:1)随着炭黑加入量的增加,Al_(2)O_(3)-SiC-C质浇注料的体积密度逐渐增大,显气孔率逐渐减小;2)Al_(2)O_(3)-SiC-C质浇注料的抗折强度和耐压强度随着炭黑加入量的增加呈现先增大后减小的趋势;3)Al_(2)O_(3)-SiC-C质浇注料的抗氧化性能和抗侵蚀性能也随着炭黑加入量的增加而逐渐提高。 展开更多
关键词 高纯炭黑 Al_(2)O_(3)-Sic-c质铁沟浇注料 抗侵蚀性能 抗氧化性能
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无水硼砂对Al_(2)O_(3)-C复合材料性能与显微结构的影响
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作者 吴嵩 韦龙杰 +3 位作者 王建筑 陈继 袁愈辉 刘诚 《耐火材料》 北大核心 2026年第1期65-68,共4页
在Al_(2)O_(3)-C复合材料中添加低熔点相,对其性能与结构改善具有重要意义。以棕刚玉、氧化铝粉、鳞片石墨为主要原料,酚醛树脂为结合剂,加入不同量的无水硼砂(加入质量分数分别为0、1%、2%、3%和4%),采用高速逆流造粒机混合,得到的混... 在Al_(2)O_(3)-C复合材料中添加低熔点相,对其性能与结构改善具有重要意义。以棕刚玉、氧化铝粉、鳞片石墨为主要原料,酚醛树脂为结合剂,加入不同量的无水硼砂(加入质量分数分别为0、1%、2%、3%和4%),采用高速逆流造粒机混合,得到的混合料在冷等静压机内成型,经250℃干燥、1000℃埋碳烧成,制备了Al_(2)O_(3)-C复合材料,研究了无水硼砂加入量对Al_(2)O_(3)-C复合材料性能及显微结构的影响。结果表明:随着无水硼砂加入量的增多,试样显气孔率显著下降,体积密度有所增加,但增加幅度较小;添加了无水硼砂的试样,细粉颗粒边界变得模糊,细粉之间孔隙部分被熔化后的无水硼砂所填充,从而使得显气孔率显著降低,常温抗折明强度显提升,抗氧化性能显著改善;与未添加无水硼砂的试样相比,加入4%(w)无水硼砂试样的显气孔率下降幅度约为25%,常温抗折强度的升高幅度约为5.6倍,氧化层面积下降约为60%。 展开更多
关键词 无水硼砂 Al_(2)O_(3)-c复合材料 性能 显微结构
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Electrospun Li_(3)V_(2)(PO_(4))_(3)/carbon nanofibers as freestanding cathodes for high-performance zinc-ion batteries
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作者 Ding Honggeng Ren Yueyue +1 位作者 Zhang Yi Zhao Hongyang 《新型炭材料(中英文)》 北大核心 2026年第1期173-183,共11页
Li_(3)V_(2)(PO_(4))_(3) is a promising high-voltage cathode for zincion batteries,but it suffers from a poor electronic conductivity and vanadium dissolution in aqueous electrolytes.The growth of carboncoated Li_(3)V_... Li_(3)V_(2)(PO_(4))_(3) is a promising high-voltage cathode for zincion batteries,but it suffers from a poor electronic conductivity and vanadium dissolution in aqueous electrolytes.The growth of carboncoated Li_(3)V_(2)(PO_(4))_(3)(LVP@C)nanoparticles on carbon nanofibers(CNFs)has been achieved by an electrospinning technique followed by calcination.The protective carbon coating prevents the aggregation of the LVP nanoparticles and suppresses V dissolution by preventing direct contact with aqueous electrolytes.The CNFs derived from the electrospun nanofibers provide a 3D network to increase the electronic conductivity of the LVP electrode,and the LVP@C-CNF hybrid film can be directly used as a freestanding cathode for zinc-ion batteries without adding conductive additives and binders.A mechanism for the formation of a uniform and continuous carbon coating has been proposed.This nanostructure,combined with the uniform and intact carbon coverage,significantly increases the electronic conductivity.This LVP@C-CNF freestanding electrode has an excellent rate capability(47.3%retention at 2 C)and cycling stability(61.2%retention after 100 cycles)within the voltage range 0.6 V to 1.95 V and is highly suitable for zinc-ion battery applications. 展开更多
关键词 Li_(3)V_(2)(PO_(4))_(3)/c Electrospinning technology carbon nanofiber films Freestanding cathode Zinc-ion batteries
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血清补体C1q、C3a、C4水平与2型糖尿病微血管病变的关系
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作者 郝建波 胡春雨 王理鑫 《分子诊断与治疗杂志》 2026年第1期63-66,共4页
目的探讨血清补体C1q、C3a、C4水平与2型糖尿病(T2DM)微血管病变(DMC)的关系。方法选取2023年1月至2025年1月郑州大学第二附属医院收治的单纯T2DM患者50例作为T2DM组,选取50例T2DM合并DMC患者作为DMC组,另选择同期50名健康体检者作为对... 目的探讨血清补体C1q、C3a、C4水平与2型糖尿病(T2DM)微血管病变(DMC)的关系。方法选取2023年1月至2025年1月郑州大学第二附属医院收治的单纯T2DM患者50例作为T2DM组,选取50例T2DM合并DMC患者作为DMC组,另选择同期50名健康体检者作为对照组,比较三组血清补体C1q、C3a、C4水平;采用Pearson相关性分析补体C1q、C3a、C4与DMC患者血糖、血脂指标的相关性;采用二元Logistic回归分析T2DM患者发生DMC的危险因素;采用受试者工作特征曲线(ROC)及曲线下面积(AUC)分析血清补体C1q、C3a、C4对T2DM患者DMC的诊断价值。结果血清补体C1q、C3a、C4水平比较:DMC组>T2DM组>对照组,差异有统计学意义(P<0.05)。DMC组与T2DM组体重指数(BMI)、病程、血糖指标空腹血糖(FPG)、糖化血红蛋白(HbA1c)、血脂指标三酰甘油(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)、胰岛素抵抗指数(HOMA-IR)、血尿酸(UA)、肌酐(Scr)比较差异有统计学意义(P<0.05)。Pearson相关性分析结果显示,T2DM发生DMC患者血清补体C1q、C3a、C4与FPG、HbA1c、TG、TC、LDL-C呈正相关性,与HDL-C呈负相关性(P<0.05)。二元Logistic回归分析结果显示,病程、FPG、HbA1c、C1q、C3a、C4为T2DM患者发生DMC的影响因素(P<0.05)。ROC曲线结果显示,C1q诊断T2DM患者发生DMC的截断值为293.65 mg/L,AUC为0.831(95%CI 0.751~0.911),灵敏度为0.841,特异度为0.800。C3a诊断T2DM患者发生DMC的截断值为394.22 mg/L,AUC为0.832(95%CI 0.748~0.916),灵敏度为0.837,特异度为0.802。C4诊断T2DM患者发生DMC的截断值为330.39 mg/L,AUC为0.824(95%CI 0.736~0.912),灵敏度为0.820,特异度为0.773。结论血清补体活化在T2DM发生DMC的病理过程中存在重要作用,血清补体C1q、C3a、C4水平升高可增加T2DM发生DMC的风险,三指标可作为T2DM发生DMC的可靠预测指标。 展开更多
关键词 2型糖尿病 糖尿病微血管病变 补体因子c1q 补体因子c3a 补体因子c4
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SH3BGRL的表达对AngⅡ诱导的H9C2心肌细胞肥大的影响
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作者 高润泽 魏小茗 +3 位作者 韩婉婷 苏莹 彭铁 朱丹 《湖北科技学院学报(医学版)》 2026年第1期44-48,共5页
目的 探讨SH3域结合谷氨酸丰富蛋白样蛋白(SH3BGRL)的表达水平对血管紧张素Ⅱ(AngⅡ)诱导的心肌细胞肥大的影响。方法 通过构建H9C2心肌细胞肥大模型,运用Western blot和RT-PCR技术分别检测SH3BGRL水平,RT-PCR技术检测心肌肥大相关标志... 目的 探讨SH3域结合谷氨酸丰富蛋白样蛋白(SH3BGRL)的表达水平对血管紧张素Ⅱ(AngⅡ)诱导的心肌细胞肥大的影响。方法 通过构建H9C2心肌细胞肥大模型,运用Western blot和RT-PCR技术分别检测SH3BGRL水平,RT-PCR技术检测心肌肥大相关标志基因ANP、BNP和β-MHC的表达情况。结果 过表达SH3BGRL后,心肌肥大相关标志基因的mRNA表达水平升高(P<0.05);而沉默SH3BGRL后,mRNA表达水平显著降低(P<0.05)。结论 SH3BGRL的表达水平与心肌肥大标志基因的表达呈正相关,有望成为治疗心肌肥大的潜在靶点,为深入研究SH3BGRL在心脏中的功能奠定了坚实基础。 展开更多
关键词 SH3域结合谷氨酸丰富蛋白样蛋白 心肌肥大 转染 H9c2细胞
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碳包覆Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)@C正极材料的制备及其钠离子电池性能
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作者 裴满 马恬 +3 位作者 陈宇 周熙 陈雷 刘炜 《电池工业》 2026年第1期17-23,共7页
采用溶胶-凝胶法成功制备了碳包覆的磷酸焦磷酸铁钠[Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)@C,缩写为NFPP@C]复合材料,其最优化热处理温度为600℃,烧结时间为10 h。将NFPP@C作为钠离子电池正极材料,分别以金属钠(Na)和硬碳(HC)作为负极材... 采用溶胶-凝胶法成功制备了碳包覆的磷酸焦磷酸铁钠[Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)@C,缩写为NFPP@C]复合材料,其最优化热处理温度为600℃,烧结时间为10 h。将NFPP@C作为钠离子电池正极材料,分别以金属钠(Na)和硬碳(HC)作为负极材料,评测其电化学储钠性能。在1.5~4.0 V(vs. Na+/Na)电压区间下,NFPP@C||Na半电池在0.1 C和5 C电流密度下的放电比容量分别为112.2 mAh/g和96.2 mAh/g,且电流密度为1 C时,循环200次后的容量保持率高达99.7%。在1.5~3.5 V(vs. HC)电压区间、1 C电流密度下,3.5 Ah全电池(即NFPP@C||HC软包单体电池)在25℃常温和45℃高温环境中循环2 800次后的容量保持率分别为92%和89.1%,表现出优异的长循环稳定性和高温工作性能。 展开更多
关键词 钠离子电池 正极材料 碳包覆 Na_(4)Fe_(3)(PO_(4))_(2)P_(2)O_(7)@c 储钠性能
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Ti_(3)C_(2)T_(x) MXene改性C-TiO_(2)/Cu_(2)O Z型异质结的构建及其光催化降解四环素
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作者 王晓云 范功端 +2 位作者 陈礼洪 牛佳 付爱民 《环境科学学报》 北大核心 2025年第12期120-134,共15页
通过煅烧Ti_(3)C_(2)T_(x) MXene制备C-TiO_(2),并采用水热法制备Cu_(2)O及不同成分比例的C-TiO_(2)/Cu_(2)O复合光催化材料.同时,对制备的MXene复合材料进行形貌、结构、比表面积和光电特性等表征分析,探讨其对四环素(TC)的光催化降解... 通过煅烧Ti_(3)C_(2)T_(x) MXene制备C-TiO_(2),并采用水热法制备Cu_(2)O及不同成分比例的C-TiO_(2)/Cu_(2)O复合光催化材料.同时,对制备的MXene复合材料进行形貌、结构、比表面积和光电特性等表征分析,探讨其对四环素(TC)的光催化降解效能,并考察其光催化活性增强机理.实验结果显示,以450℃煅烧制备的C掺杂TiO_(2)以表面掺杂或负载为主,保持了部分Ti_(3)C_(2)T_(x)特性,更有利于可见光的吸收.对于50%C-TiO_(2)/Cu_(2)O而言,C掺杂可有效减小TiO_(2)的能带间隙,C-TiO_(2)与Cu_(2)O形成以C层为媒介的Z型异质结构,可有效减小光生e^(-)-h^(+)的复合,在pH=7.0时对TC的光催化降解效率为95.5%,其反应速率常数分别是C-TiO_(2)和Cu_(2)O的6.8和4.5倍.经过5次循环重复实验,50%C-TiO_(2)/Cu_(2)O MXene复合材料总体效能与稳定性良好,且在较宽泛pH范围(3~11)内对TC保持优异降解率,具有良好的实际应用前景.淬灭实验及电子顺磁共振测试结果显示,h^(+)是50%C-TiO_(2)/Cu_(2)O降解TC过程中最主要的活性物种,其次为^(1)O_(2)和^(·)O_(2)^(-).采用密度泛函理论(DFT)计算福井函数(Fukui function)预测了活性物种对TC分子的攻击位置,结合高效液相色谱-质谱联用技术(HPLC-MS)得出TC的光降解过程包括去甲基化、去甲酰化、开环反应、脱水、脱氨基等反应,并最终被氧化为小分子有机物、二氧化碳和水. 展开更多
关键词 Ti_(3)c_(2)T_(x)MXene改性 c-tio_(2)/cu_(2)O Z型异质结 四环素 光催化降解机理 密度泛函理论 降解产物
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C/TiO_(2-x)/Al_(2)O_(3)的原位制备及可见光催化性能研究
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作者 谭灵 董伟霞 +2 位作者 罗婷 李萍 顾幸勇 《中国陶瓷》 北大核心 2025年第12期1-10,共10页
开发经济且高效的可见光光催化剂是当前研究热点之一。本研究采用钛酸铝(Al_(2)TiO_(5))与淀粉混合样在缺氧条件下原位热分解制备C/TiO_(2-x)/Al_(2)O_(3)可见光催化剂。系统考察了不同缺氧气氛(炭粉埋烧、H_(2)、N_(2))下所得材料对亚... 开发经济且高效的可见光光催化剂是当前研究热点之一。本研究采用钛酸铝(Al_(2)TiO_(5))与淀粉混合样在缺氧条件下原位热分解制备C/TiO_(2-x)/Al_(2)O_(3)可见光催化剂。系统考察了不同缺氧气氛(炭粉埋烧、H_(2)、N_(2))下所得材料对亚甲基蓝(MB)溶液的光催化降解性能,并解析了其高效光催化性能的机理。结果表明,在可见光照射180 min后,炭粉埋烧条件下原位热分解所制备的C/TiO_(2-x)/Al_(2)O_(3)-Burying、TiO_(2-x)/Al_(2)O_(3)-Burying、C/TiO_(2-x)/Al_(2)O_(3)-H_(2)和Fixing mixture样品对MB染料的降解率η分别为95.56%、90.03%、73.33%和60.07%。其优异性能主要归因于片状碳结构与TiO_(2)的有效耦合及适量氧空位的引入,增强了光生电子–空穴对的分离效率,为高效TiO_(2)基可见光催化材料的规模化制备提供了新思路。 展开更多
关键词 原位热分解 c/tio_(2-x)/Al_(2)O_(3) 可见光 光催化性能
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Synthesis of C2-Spiroindolines Based on the Cascade Reaction of 2-Aryl-3H-indoles with Cyclopropanols
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作者 Xueying Yang Yuanshuang Xu +1 位作者 Xinying Zhang Xuesen Fan 《有机化学》 北大核心 2025年第2期694-706,共13页
A novel synthesis of C2-spiroindoline derivatives based on the cascade reaction of 2-aryl-3H-indoles with cyclo- propanols is presented. The formation of product involves Rh(III)-catalyzed aryl C(sp2)—H bond alkylati... A novel synthesis of C2-spiroindoline derivatives based on the cascade reaction of 2-aryl-3H-indoles with cyclo- propanols is presented. The formation of product involves Rh(III)-catalyzed aryl C(sp2)—H bond alkylation of 2-aryl- 3H-indole, which is followed by intramolecular spiroannulation. In this tandem process, cyclopropanol acts as not only an alkylating agent but also a masked nucleophile to take part in the construction of the spirocyclic scaffold. Meanwhile, air acts as an economical and sustainable oxidant to promote the regeneration of the active catalyst. By using this method, hybrid compounds containing the central scaffolds of some clinical drugs were prepared effectively. In general, this newly developed method has advantages such as easily obtainable substrates, concise synthetic procedure, excellent atom-economy, good compatibility with diverse functional groups and ready scalability. 展开更多
关键词 c2-spiroindolines SYNTHESIS c-H bond activation cascade reaction 2-aryl-3H-indoles cYcLOPROPANOLS
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Collaborative photocatalytic C-C coupling with Cu and P dual sites to produce C_(2)H_(4) over CuxP/g-C_(3)N_(4) heterojunction 被引量:1
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作者 Dongxiao Wen Nan Wang +2 位作者 Jiahe Peng Tetsuro Majima Jizhou Jiang 《Chinese Journal of Catalysis》 2025年第2期58-74,共17页
Light-driven CO_(2) reduction reaction(CO_(2)RR)to value-added ethylene(C2H4)holds significant promise for addressing energy and environmental challenges.While the high energy barriers for*CO intermediates hydrogenati... Light-driven CO_(2) reduction reaction(CO_(2)RR)to value-added ethylene(C2H4)holds significant promise for addressing energy and environmental challenges.While the high energy barriers for*CO intermediates hydrogenation and C–C coupling limit the C_(2)H_(4)generation.Herein,CuxP/g-C_(3)N_(4) heterojunction prepared by an in-situ phosphating technique,achieved collaborative photocatalytic CO_(2) and H2O,producing CO and C_(2)H_(4)as the main products.Notably,the selectivity of C_(2)H_(4)produced by CuxP/g-C_(3)N_(4) attained to 64.25%,which was 9.85 times that of CuxP(6.52%).Detailed time-resolution photoluminescence spectra,femtosecond transient absorption spectroscopy tests and density functional theory(DFT)calculation validate the ultra-fast interfacial electron transfer mechanism in CuxP/g-C_(3)N_(4) heterojunction.Successive*H on P sites caused by adsorbed H2O splitting with moderate hydrogenation ability enables the multi-step hydrogenation during CO_(2)RR process over CuxP/g-C_(3)N_(4).With the aid of mediated asymmetric Cu and P dual sites by g-C_(3)N_(4) nanosheet,the produced*CHO shows an energetically favorable for C–C coupling.The coupling formed*CHOCHO further accepts photoexcited efficient e–and*H to deeply produce C_(2)H_(4)according to the C^(2+)intermediates,which has been detected by in-situ diffuse reflectance infrared Fourier transform spectroscopy and interpreted by DFT calculation.The novel insight mechanism offers an essential understanding for the development of CuxP-based heterojunctions for photocatalytic CO_(2) to C^(2+)value-added fuels. 展开更多
关键词 Photocatalytic cO_(2) reduction c-c coupling Ethylene cu_(x)P/g-c_(3)N_(4)heterojunction
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Inhibition of the Arp2/3 Complex Attenuates Angiotensin Ⅱ-Induced Cardiomyocyte Hypertrophy
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作者 LING Li PAN Cong-Bin +2 位作者 WAN Lu-Xuan YANG Zhuang-Zhuang REN Zhan-Hong 《中国生物化学与分子生物学报》 北大核心 2025年第9期1332-1341,I0003-I0007,共15页
Pathological cardiac hypertrophy is an early and significant cardiac structural characteristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarge... Pathological cardiac hypertrophy is an early and significant cardiac structural characteristic that contributes to the onset and progression of heart failure(HF).Its mainly structural feature is the abnormally enlarged cardiomyocyte.Effective intervention targets for abnormally enlarged cardiomyocyte remain to be identified.Previous studies have shown that the cellular shape and size can be regulated by the actin related protein 2/3(Arp2/3)complex,which is an actin-binding protein complex involved in the actin nucleation and assembly.However,the roles of the Arp2/3 complex in cardiomyocyte hypertrophy remain unknown.Here our study identifies its novel roles in the occurrence and development of cardiomyocyte hypertrophy.We found that mRNA levels of all subunits from the Arp2/3 complex are significantly upregulated(P<0.05)in the angiotensin Ⅱ(Ang Ⅱ)-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy.Further studies showed that siRNA-directed ARPC 2 silencing inhibits the reactivation of fetal genes and enlargement of cardiomyocyte area induced by Ang Ⅱ in neonatal rat primary cardiomyocytes(NRCMs)and H9c2 cells(P<0.05).In addition,the upstream activators of the Arp2/3 complex including SH3 protein interacting with Nck,90 kD(SPIN90)and Ras-related C3 botulinum toxin substrate 1(Rac1)/WASp family Verprolin-homologous protein-2(WAVE-2)are upregulated(P<0.05)in Ang Ⅱ-induced neonatal rat primary and H9c2 cardiomyocyte hypertrophy,indicating the excessive activation of the Arp2/3 complex.We further show that CK666,a specific Arp2/3 complex inhibitor,prevents the reactivation of fetal genes and the enlargement of cardiomyocyte area induced by Ang Ⅱ in NRCMs and H9c2 cells(P<0.05).Our results reveal that the Arp2/3 complex plays a crucial role in Ang Ⅱ-induced cardiomyocyte hypertrophy,which is beneficial to further studies about the molecular mechanisms by which the Arp2/3 complex regulates pathological cardiac hypertrophy. 展开更多
关键词 cardiomyocyte hypertrophy Arp2/3 complex angiotensinⅡ(AngⅡ) neonatal rat primary cardiomyocytes(NRcMs) H9c2 cells
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工艺参数对Al_(2)O_(3)-C耐火材料抗氧化性和抗水化性的影响 被引量:1
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作者 张瑞 孙旭东 +5 位作者 魏瀚 袁彪 王俊涛 袁林 刘士范 陈松林 《耐火材料》 北大核心 2025年第1期65-69,共5页
为了研究各因素对Al_(2)O_(3)-C耐火材料抗氧化和抗水化性能的影响,以优化其制备工艺,以板状刚玉、Al粉、电熔锆刚玉、活性氧化铝粉、鳞片石墨为主要原料,使用热固性酚醛树脂为结合剂,采用液压成型制成?50 mm×50 mm的圆柱体试样,... 为了研究各因素对Al_(2)O_(3)-C耐火材料抗氧化和抗水化性能的影响,以优化其制备工艺,以板状刚玉、Al粉、电熔锆刚玉、活性氧化铝粉、鳞片石墨为主要原料,使用热固性酚醛树脂为结合剂,采用液压成型制成?50 mm×50 mm的圆柱体试样,在埋碳气氛下对试样进行了热处理。选取Al粉加入量(加入质量分数分别为6%、9%和12%)、石墨加入量(加入质量分数分别为5%、15%和25%)、热处理温度(680、950、1 500℃)和保温时间(3、6、9 h)为研究因素,每个因素选取3个水平进行正交设计,分析了其对Al_(2)O_(3)-C耐火材料抗氧化和抗水化性能的影响。结果表明:1)Al粉加入量和石墨加入量为影响抗氧化性能的主要因素,而热处理温度和保温时间为次要因素;2)Al粉加入量和热处理温度是影响抗水化性能的主要因素,而石墨加入量和保温时间为次要因素;3)综合考虑,最优工艺为:Al粉加入量9%(w),石墨加入量5%(w),热处理温度1 500℃,保温时间6 h,制备的试样中存在柱状的Al_(4)O_(4)C,能够显著提高材料的抗氧化和抗水化性能。 展开更多
关键词 Al_(2)O_(3)-c耐火材料 Al_(4)O_(4)c 抗水化性能 抗氧化性能
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Effect of Cr_(2)O_(3)/Cr_(3)C_(2)additions on mechanical and tribological properties of Ti(C,N)-based cermets
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作者 Mei-ling LIU Ya-jing CAO +1 位作者 Wan-xiu HAI Yu-hong CHEN 《Transactions of Nonferrous Metals Society of China》 2025年第2期525-537,共13页
Cr_(2)O_(3)was used as grain inhibitor in Ti(C,N)-based cermets with vacuum sintering.The microstructure and mechanical and tribological properties of cermets with Cr_(2)O_(3)and Cr_(3)C_(2)were investigated.The resul... Cr_(2)O_(3)was used as grain inhibitor in Ti(C,N)-based cermets with vacuum sintering.The microstructure and mechanical and tribological properties of cermets with Cr_(2)O_(3)and Cr_(3)C_(2)were investigated.The results show that adding Cr_(2)O_(3)promotes a gray core/gray rim structure formation and finer size of Ti(C,N)hard phase.Compared with the cermet with an equal Cr_(3)C_(2)addition,the cermet with 0.6 wt.%Cr_(2)O_(3)exhibits 16.5%higher transverse rupture strength.This enhancement is likely due to the smaller lattice misfit at the core/rim interface and more uniform Cr distribution in the binder.Additionally,at room temperature(25℃)and 800℃,Cr_(2)O_(3)-containing cermets demonstrate lower coefficients of friction and volume wear ratios than Cr_(3)C_(2)-containing cermets,with the wear ratio difference reaching an order of magnitude.Scanning electron microscopy and X-ray photoelectron spectroscopy results further confirm more oxidation wear in Cr_(2)O_(3)-containing cermets than in Cr_(3)C_(2)-containing cermets. 展开更多
关键词 TI(c N) cr_(2)O_(3) grain inhibitor mechanical properties tribological properties
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circNR3C2 promotes chondrogenic differentiation and cartilage repair of human adipose-derived stem cells via the hsa-miR-647/SOX9 pathway
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作者 Dabiao Hou Huajun Wang +3 位作者 Hao Guo Dongbin Luo Xiaofei Zheng Simin Luo 《Animal Models and Experimental Medicine》 2025年第12期2209-2221,共13页
Background:Human adipose-derived stem cells(hADSCs)are seed cells with application prospects in cartilage repair.However,the mechanism of hADSC chondrogenic differentiation is still unclear.This study identifies a nov... Background:Human adipose-derived stem cells(hADSCs)are seed cells with application prospects in cartilage repair.However,the mechanism of hADSC chondrogenic differentiation is still unclear.This study identifies a novel circRNA,circNR3C2,which is significantly upregulated during the chondrogenic differentiation of hADSCs.Methods:To analyze their role in hADSC chondrogenic differentiation,hADSCs were separated and identified by flow cytometry.Thereafter,we conducted Alcian Blue staining to assess chondrogenic differentiation levels.Additionally,RT-qPCR was carried out to detect levels of the cartilage-related genes COL2,Aggrecan and SOX9.Moreover,overlapping target SOX9 and circNR3C2 miRNAs were detected by bioinformatics and luciferase analyses.Finally,the role of circNR3C2 was confirmed in vivo using animal models.Results:We confirmed that the cell surface receptors CD44,CD90 and CD105 were positively expressed on hADSCs,and their cartilage differentiation levels dramatically increased after 2 weeks.Expression of the cartilage-related genes COL2 and Aggrecan and circNR3C2 also markedly increased.CircNR3C2 overexpression enhanced cartilage differentiation of hADSCs,while up-regulating COL2,SOX9 and Aggrecan.Bioinformatics analysis identified hsa-miR-647 as the target miRNA of circ-NR3C2 and SOX9.Hsa-miR-647 overexpression in hADSCs can antagonize the effect of circNR3C2 on chondrogenic differentiation,and reverse its effect on regulating the expression of COL2,Aggrecan,and SOX9.We also showed that hADSCs overexpressing circNR3C2 promote cartilage repair in vivo.Conclusions:We show that circNR3C2 modulates SOX9 expression to promote hsamiR-647-mediated hADSC chondrogenic differentiation;targeting circNR3C2 may help to develop new treatments to manage cartilage-related disorders. 展开更多
关键词 cartilage repair chondrocyte differentiation circNR3c2 hADScs hsa-miR-647 SOX9
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Aloin blocks the malignant behavior of lung squamous cell carcinoma cells and M2 macrophage polarization by modulating the NR3C2/MT1M axis
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作者 Ying-na Chen Jie-ya Lu +2 位作者 Cheng-feng Gao Zhi-ruo Fang Yan Zhou 《Journal of Integrative Medicine》 2025年第2期195-208,共14页
Objective:Aloin,the main active component in Aloe vera(L.)Burm.f.,has shown promising anti-tumor effects.This study investigated the impact of aloin in lung squamous cell carcinoma(LUSC)and explored its functional mec... Objective:Aloin,the main active component in Aloe vera(L.)Burm.f.,has shown promising anti-tumor effects.This study investigated the impact of aloin in lung squamous cell carcinoma(LUSC)and explored its functional mechanism.Methods:We analyzed the viability,migration,invasion,proliferation,and apoptosis of two LUSC cell lines after treatment with aloin.Target molecules of aloin and downstream target transcripts of nuclear receptor subfamily 3 group C member 2(NR3C2)were predicted by bioinformatics.The biological functions of NR3C2 and metallothionein 1M(MT1M)in the malignant properties of LUSC cells were determined.A co-culture system of LUSC cells with monocyte-derived macrophages was constructed.Mouse xenograft tumor models were generated to analyze the functions of aloin and NR3C2 in the tumorigenic activity of LUSC cells and macrophage polarization in vivo.Results:Aloin suppressed malignant properties of LUSC cells in vitro.However,these effects were negated by the silencing of NR3C2.NR3C2 was found to activate MT1M transcription by binding to its promoter.Additional upregulation of MT1M suppressed the malignant behavior of LUSC cells augmented by NR3C2 silencing.Analysis of the M1 and M2 markers/cytokines in the macrophages or the culture supernatant revealed that aloin treatment or MT1M overexpression in LUSC cells enhanced M1 polarization while suppressing M2 polarization of macrophages,whereas NR3C2 silencing led to reverse trends.Consistent findings were reproduced in vivo.Conclusion:This study demonstrated that aloin activates the NR3C2/MT1M axis to suppress the malignant behavior of LUSC cells and M2 macrophage polarization.Please cite this article as:Chen YN,Lu JY,Gao CF,Fang ZR,Zhou Y.Aloin blocks the malignant behavior of lung squamous cell carcinoma cells and M2 macrophage polarization by modulating the NR3C2/MT1M axis. 展开更多
关键词 ALOIN NR3c2 MT1M MAcROPHAGES Lung squamous cell carcinoma
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