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Hierarchical Manufacturing of Anisotropic and High-Efficiency Electromagnetic Interference Shielding Modules for Smart Electronics
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作者 Shaohong Shi Siwen Deng +6 位作者 Yuheng Jiang Jiabin Chen Lukas Sporrer Fangchao Cheng Quanquan Guo Jingjing Jing Yinghong Chen 《Nano-Micro Letters》 2026年第6期125-139,共15页
To shield electronics from complicated electromagnetic environments caused by wireless electromagnetic waves,achieving elaborately structural manufacturing while not sacrificing electromagnetic interference shielding ... To shield electronics from complicated electromagnetic environments caused by wireless electromagnetic waves,achieving elaborately structural manufacturing while not sacrificing electromagnetic interference shielding performances remains crucial challenges.Herein,we propose a hierarchical manufacturing method that combines the use of 3D printing shear flow field and layer-by-layer assembly for fabricating the structurally customizable and multifunctional polylactic acid@graphene nanoparticle(PLA@GNs)materials.The dynamic behavior of polymer fluids is firstly explored via computational fluid dynamic simulation,and a Weissenberg number is employed to quantitatively analyze the disordered-to-ordered structural evolution of molecular chains and nanoparticles,allowing to tailor the micro-scale ordered structures.Subsequently,the macro-scale 3D architectures of PLA@GNs modules are fabricated by layer-by-layer assembly.Owing to the aligned GNs,the shielding performance reaches 41.2 d B,simultaneously accompanied by a directional thermal conductivity of 3.2 W m^(-1)K^(-1).Moreover,the potential application of 3D-printed shielding modules in specific civilian frequency bands such as 4G(1800–2100 MHz),Bluetooth(2402–2480 MHz),and 5G(3300–3800 MHz)is fully demonstrated.Overall,this work not only establishes a universal methodology about 3D printing shear flow field-driven orientation of two-dimensional nanoparticles within polymer fluids,but also gives a scientific method for advanced manufacturing of the next-generation electromagnetic functional modules for smart electronics. 展开更多
关键词 3D printing Graphene nanoparticles Hierarchical manufacturing Electromagnetic interference shielding Thermal management
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Interfacial design and thermoelectric properties of C_(3)N_(4)-C_(20) molecular junctions based on quantum interference
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作者 Shutao Hu Meng Qian +1 位作者 Gang Zhang Bei Zhang 《Chinese Physics B》 2025年第6期109-115,共7页
Quantum interference effect serves as a critical strategy for addressing incorrect energy level alignment between frontier molecular orbitals and electrodes in molecular junctions. Weak-coupling structures offer an ef... Quantum interference effect serves as a critical strategy for addressing incorrect energy level alignment between frontier molecular orbitals and electrodes in molecular junctions. Weak-coupling structures offer an effective approach to suppress phonon thermal conductance. The thermoelectric properties of pure C_(3)N_(4) nanoribbon devices and C_(3)N_(4)-C_(20) molecular junctions are systematically investigated based on density functional theory(DFT) combined with nonequilibrium Green's function(NEGF) formalism. The results show that pure C_(3)N_(4) nanoribbon devices have superior charge transport capabilities and excellent Seebeck coefficients. A remarkable thermoelectric figure of merit(ZT = 0.98)is achieved near 0.09 e V. The pronounced scattering effect induced by embedding a C_(20) molecule in the center of the C_(3)N_(4) nanoribbon significantly suppresses phonon transport. A maximum ZT value of 1.68 is observed at 0.987 e V. The electron mobility of C_(3)N_(4)-C_(20)-par is effectively increased due to quantum interference effect which greatly improves the alignment between the C_(20) molecule's frontier orbital energy level and C_(3)N_(4) electrodes. The C_(3)N_(4)-C_(20)-van der Waals(vd W) molecular junction allows very few phonons to pass through the C_(20) molecule from the left electrode to the right electrode. As a result, the C_(3)N_(4)-C_(20)-vd W junction achieves an excellent ZT value of 3.82 near the Femi level. 展开更多
关键词 quantum interference effect C_(3)N_(4)-C_(20)molecular junctions thermoelectric properties first-principles theory
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基于香豆素的新型Fe^(3+)荧光探针的构建及其应用性能研究
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作者 孟超鹏 张悦然 +5 位作者 周永鑫 唐勇军 李杰 吕琳 高云 高妍 《分析测试学报》 北大核心 2026年第2期311-319,共9页
该文设计并合成了一种以香豆素为荧光团、安替比林为识别基团的新型香豆素类荧光探针CAM。在Fe^(3+)存在下,探针荧光完全猝灭,可归因于识别Fe^(3+)后形成的CAM-Fe^(3+)引发的螯合荧光猝灭效应(CHEQ)。探针CAM识别Fe^(3+)的检出限为5.27&... 该文设计并合成了一种以香豆素为荧光团、安替比林为识别基团的新型香豆素类荧光探针CAM。在Fe^(3+)存在下,探针荧光完全猝灭,可归因于识别Fe^(3+)后形成的CAM-Fe^(3+)引发的螯合荧光猝灭效应(CHEQ)。探针CAM识别Fe^(3+)的检出限为5.27×10^(-8) mol/L。通过高分辨质谱(HR-MS)考察了探针对Fe^(3+)的响应机制。CAM探针展现出对目标离子的快速响应(80 s)、良好的水溶性及抗干扰能力强的特性。并结合手机智能识别技术,将探针CAM“试纸”用于对自来水和湖水中Fe^(3+)的分析检测。同时该探针已成功应用于细胞和小鼠的生物成像研究。 展开更多
关键词 香豆素 荧光探针 fe^(3+) 智能识别 实际水样 生物成像
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S:BiFeO_(3)/Fe_(2)O_(3)复合材料的制备及其光电化学性能研究
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作者 周艳红 王德宝 《现代化工》 北大核心 2026年第3期211-217,共7页
通过溶剂热法成功制备了S:BiFeO_(3)/Fe_(2)O_(3)复合材料,采用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)等对复合材料进行物相、形貌表征。通过电化学工作站测... 通过溶剂热法成功制备了S:BiFeO_(3)/Fe_(2)O_(3)复合材料,采用X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和高分辨透射电子显微镜(HRTEM)等对复合材料进行物相、形貌表征。通过电化学工作站测试复合材料的线性伏安曲线(LSV)、交流阻抗(EIS)和莫特-肖特基测试(M-S),考察了复合材料光电化学性能的增强机制。实验表明,1.23 V(vs.RHE)时,S:BiFeO_(3)/Fe_(2)O_(3)复合材料的光电流密度(约250μA/cm^(2))大约是Fe_(2)O_(3)(约30μA/cm^(2))的8.3倍。S掺杂的BiFeO_(3)作为空穴注入层,促使复合材料的表面空穴注入效率比Fe_(2)O_(3)提高了1.5倍。而且,S:BiFeO_(3)催化剂层与Fe_(2)O_(3)之间形成了内建电场,降低了界面电荷转移电阻,并有效加速了界面光生电子-空穴对的分离。这项工作为开发高效光电化学电极提供了一种有前景的策略,并有可能应用于其他半导体的光电水分解合成策略。 展开更多
关键词 光电催化 水分解 空穴注入效率 内建电场 S:BifeO_(3) fe_(2)O_(3)
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Fe^(3+)掺杂TiO_(2)的制备及可见光催化降解亚甲基蓝
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作者 曾言 张涛 李政 《辽宁化工》 2026年第2期270-272,共3页
本文以钛酸四丁酯为钛源、Fe(NO_(3))_(3)·9H_(2)O为铁元素添加剂,制备了Fe^(3+)掺杂TiO_(2)光催化材料,用于可见光降解亚甲基蓝。通过XRD和SEM对光催化材料进行表征分析,进一步考察光催化剂投加量、亚甲基蓝初始质量浓度及初始pH... 本文以钛酸四丁酯为钛源、Fe(NO_(3))_(3)·9H_(2)O为铁元素添加剂,制备了Fe^(3+)掺杂TiO_(2)光催化材料,用于可见光降解亚甲基蓝。通过XRD和SEM对光催化材料进行表征分析,进一步考察光催化剂投加量、亚甲基蓝初始质量浓度及初始pH对光催化效果的影响。结果表明:Fe^(3+)掺杂TiO_(2)光催化材料由锐钛矿型TiO_(2)粒子和金红石型TiO_(2)粒子组成,为表面光滑的片状结构,粒径大多在50μm左右。当Fe^(3+)掺杂TiO_(2)光催化材料投加量为0.15 g、亚甲基蓝初始质量浓度为10 mg·L^(-1)、初始pH为8时,亚甲基蓝的降解率达到98.02%。 展开更多
关键词 fe^(3+)掺杂TiO_(2) 光催化 亚甲基蓝
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Fe掺杂g-C_(3)N_(5)活化过二硫酸盐光催化降解RhB
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作者 刘思乐 李佳 +1 位作者 韩悦 单译 《印染》 北大核心 2026年第4期70-74,共5页
通过沉淀煅烧法制备了Fe掺杂富氮石墨相氮化碳光催化剂(Fe/g-C_(3)N_(5)),并采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外可见漫反射光谱(UV-vis DRS)、稳态荧光光谱(PL)和电化学交流阻抗谱(EIS)等方法对Fe/g-C_(3)N_(5)光... 通过沉淀煅烧法制备了Fe掺杂富氮石墨相氮化碳光催化剂(Fe/g-C_(3)N_(5)),并采用X射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)、紫外可见漫反射光谱(UV-vis DRS)、稳态荧光光谱(PL)和电化学交流阻抗谱(EIS)等方法对Fe/g-C_(3)N_(5)光催化剂的物相晶型、微观形貌、能带结构、光电子-空穴复合情况和导电性进行表征。以罗丹明B(RhB)为模拟污染物,研究了可见光照射下Fe/g-C_(3)N_(5)活化过二硫酸盐(PDS)的光催化活性和循环使用稳定性,并通过活性基团捕获试验探究了光催化体系中活性基团的作用。结果表明:Fe/g-C_(3)N_(5)光催化剂呈堆叠的纳米片结构;Fe/g-C_(3)N_(5)活化PDS可见光体系照射60 min,RhB染液的光催化降解率达到95.9%,循环使用5次后仍具有良好的光催化活性。活性基团捕获结果表明,体系中的主要活性基团为h^(+)、・OH和・SO_(4)^(-)。 展开更多
关键词 fe/g-C_(3)N_(5) 光催化 富氮石墨相氮化碳 过二硫酸盐 罗丹明B
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3D打印聚合物转化SiOC(Fe)陶瓷及其结构性能
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作者 江龙 龙重雨 +2 位作者 刘志远 刘长勇 陈张伟 《航空材料学报》 北大核心 2026年第1期89-99,共11页
将聚合物前驱体转化SiOC(Fe)陶瓷技术与光固化3D打印技术结合,成功开发出一种乙烯基二茂铁(VcFe)改性的聚合物前驱体光敏树脂。该树脂兼具较低黏度、高光敏性和良好固化强度,能够成形具有复杂几何结构和微纳特征的前驱体模型。在1000℃... 将聚合物前驱体转化SiOC(Fe)陶瓷技术与光固化3D打印技术结合,成功开发出一种乙烯基二茂铁(VcFe)改性的聚合物前驱体光敏树脂。该树脂兼具较低黏度、高光敏性和良好固化强度,能够成形具有复杂几何结构和微纳特征的前驱体模型。在1000℃氩气气氛中裂解,获得形状完整、收缩均匀的SiOC(Fe)陶瓷部件(质量保留率为45.27%,密度为1.89 g/cm^(3),线收缩率为32.94%)。同时系统研究裂解过程中的物相演变规律与体积收缩规律特性,并表征陶瓷产物硬度(1000℃裂解后硬度达5.93 GPa)。本研究验证光固化3D打印技术结合聚合物前驱体转化陶瓷技术制备复杂结构SiOC(Fe)陶瓷的可行性,为该技术的应用提供指导。 展开更多
关键词 3D打印 聚合物前驱体 SiOC(fe)陶瓷
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Rice Repetitive DNA Sequence RRD3:a Plant Promoter and Its Application to RNA Interference
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作者 仲健 王宏斌 +2 位作者 张党权 刘兵 王金发 《Journal of Genetics and Genomics》 SCIE CAS CSCD 北大核心 2007年第3期258-266,共9页
Previously, a moderately repetitive DNA sequence (RRD3) was cloned from rice (Oryza sativa L.) by DNA renaturation kinetics. Sequence analysis revealed several conserved promoter motifs, including four TATA-boxes ... Previously, a moderately repetitive DNA sequence (RRD3) was cloned from rice (Oryza sativa L.) by DNA renaturation kinetics. Sequence analysis revealed several conserved promoter motifs, including four TATA-boxes and a CAAT-box, and promoter activity was shown in Escherichia coli and mammalian expression systems. Here, we inserted the RRD3 fragment into the plant promoter-capture vector, pCAMBIA1391Z, and examined whether the RRD3 fragment has promoter activity in plants. Transgenic tobacco and rice calli both showed β-glucuronidase (GUS) activity, indicating that RRD3 can act as a promoter in both monocot and dicot plants. Based on the promoter characteristic of RRD3, we designed a plant universal binary vector, pCRiRRD3, which is suitable for performing researches on plant RNA interference. This vector has two multiple cloning sites to facilitate sense and antisense cloning of the target sequence, separated by an intron fragment of 200 bp. The efficiency of the vector for gene silencing was assayed by histochemical and quantitative fluorometric GUS assays in transgenic tobacco. These research results suggested that this plant RNAi vector pCRiRRD3 can effectively perform gene silencing researches on both monocot and dicot plants. 展开更多
关键词 RRD3 PROMOTER GUS histochemical assay quantitative fluorometric GUS assay RNA interference
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3D Printed Integrated Gradient-Conductive MXene/CNT/Polyimide Aerogel Frames for Electromagnetic Interference Shielding with Ultra-Low Reflection 被引量:25
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作者 Tiantian Xue Yi Yang +5 位作者 Dingyi Yu Qamar Wali Zhenyu Wang Xuesong Cao Wei Fan Tianxi Liu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第3期332-345,共14页
Construction of advanced electromagnetic interference(EMI)shielding materials with miniaturized,programmable structure and low reflection are promising but challenging.Herein,an integrated transition-metal carbides/ca... Construction of advanced electromagnetic interference(EMI)shielding materials with miniaturized,programmable structure and low reflection are promising but challenging.Herein,an integrated transition-metal carbides/carbon nanotube/polyimide(gradient-conductive MXene/CNT/PI,GCMCP)aerogel frame with hierarchical porous structure and gradient-conductivity has been constructed to achieve EMI shielding with ultra-low reflection.The gradient-conductive structures are obtained by continuous 3D printing of MXene/CNT/poly(amic acid)inks with different CNT contents,where the slightly conductive top layer serves as EM absorption layer and the highly conductive bottom layer as reflection layer.In addition,the hierarchical porous structure could extend the EM dissipation path and dissipate EM by multiple reflections.Consequently,the GCMCP aerogel frames exhibit an excellent average EMI shielding efficiency(68.2 dB)and low reflection(R=0.23).Furthermore,the GCMCP aerogel frames with miniaturized and programmable structures can be used as EMI shielding gaskets and effectively block wireless power transmission,which shows a prosperous application prospect in defense industry and aerospace. 展开更多
关键词 3D printing MXene/CNT/Polyimide aerogel Gradient-conductive Electromagnetic interference shielding
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Lentivirus-mediated shRNA interference targeting STAT3 inhibits human pancreatic cancer cell invasion 被引量:19
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作者 Guang Yan Chen Huang Jun Cao Ke-Jian Huang Tao Jiang Zheng-Jun Qiu 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第30期3757-3766,共10页
AIM: To investigate RNA interference targeting signal transducer and activator of transcription-3 (STAT3) on invasion of human pancreatic cancer cells.METHODS: We constructed three plasmids of RNA interference tar... AIM: To investigate RNA interference targeting signal transducer and activator of transcription-3 (STAT3) on invasion of human pancreatic cancer cells.METHODS: We constructed three plasmids of RNA interference targeting the STAT3 gene. After LV (lentivirus)-STAT3siRNA (STAT3 small interfering RNA) the vector was transfected into the human pancreatic cell line, SW1990 and cell proliferation was measured by the MTT assay. Flow cytometry was used to assess cell cycle. Vascular endothelial growth favor (VEGF) and matrix metalloproteinase-2 (MMP-2) mRNA and protein expression were examined by quantitative PCR and western blotting, respectively. The invasion ability of SW1990 cells was determined by cell invasion assay.RESULTS: We successfully constructed the LVSTAT3siRNA lentivirus vector and proved that it can suppress expression of STAT3 gene in SW1990 cells. RNA interference of STAT3 by the LV-STAT3siRNA construct significantly inhibited the growth of SW1990 cells, in addition to significantly decreasing both VEGF and MMP-2 mRNA and protein expression. Moreover, suppression of STAT3 by LV-STAT3siRNA decreased the invasion ability of SW1990 cells.CONCLUSION: The STAT3 signaling pathway may provide a novel therapeutic target for the treatment of pancreatic cancer since it inhibits the invasion ability of pancreatic cancer cells. 展开更多
关键词 Signal transducer and activator of transcription3 RNA interference Lentivirus vector Pancreatic cancercells INVASION
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Lentivirus vectors construction of SiRNA targeting interference GPC3 gene and its biological effects on liver cancer cell lines Huh-7 被引量:8
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作者 Chang-Jiang Lei Chun Yao +5 位作者 Qing-Yun Pan Hao-Cheng Long Lei Li Shu-Ping Zheng Cheng Zeng Jian-Bin Huang 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第10期780-786,共7页
Objective:To build GPC3 gene short hairpin interference RNA(shRNA)slow virus veclor.observe expression of Huh-7 GPC3 gene in human liver cell line proliferation apoptosis and the effect of GPC3 gene influencing on liv... Objective:To build GPC3 gene short hairpin interference RNA(shRNA)slow virus veclor.observe expression of Huh-7 GPC3 gene in human liver cell line proliferation apoptosis and the effect of GPC3 gene influencing on liver cancer cell growth,and provide theoretical basis for genc therapy of liver cancer.Methods:Hepatocellular carcinoma cell line Huh-7 wsa transfected by a RNA interference technique.GPC3 gene expression in a variety of liver cancer cell lines was detected by fluorescence quantitative PCR.Targeted GPC3 gene seqnences of small interfering RNA(siRNA)PGC-shRNA-GPC3 were restructured.Stable expression cell linse of siRNA were screened and established with the heplp of liposomes(lipofectamine^(TM2000))as carrier transfcetion of human liver cell lines.In order to validate siRNA interference efficiency.GPC3 siRNA mRNA expression was detected after transfection by using RT-PCR and Western blot.The absorbance value of the cells of blank group,untransfection group and transfection group,the cell cycle and cell apoptosis were calculated,and effects of GPC3 gene nn Huh-7 cell proliferation and apoptosis were observed.Results:In the liver cancer cell lines Huh-7 GPC3 gene showed high expression.PGC-shRNA-GPC3 recombinant plasmid was constructde successfully via sequencing validation.Stable recombinant plasmid transfected into liver cancer cell linse Huh-7can obviously inhibit GPC3 mRNA expression level.Conclusions:The targeted GPC3 siRNA can effectively inhibit the expression of GPC3. 展开更多
关键词 GPC3 GENE SLOW virus CARRIER Liver cancer cell lines RNA interference
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3D‑Printed Carbon‑Based Conformal Electromagnetic Interference Shielding Module for Integrated Electronics 被引量:8
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作者 Shaohong Shi Yuheng Jiang +5 位作者 Hao Ren Siwen Deng Jianping Sun Fangchao Cheng Jingjing Jing Yinghong Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第5期87-101,共15页
Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electroni... Electromagnetic interference shielding(EMI SE)modules are the core com-ponent of modern electronics.However,the tra-ditional metal-based SE modules always take up indispensable three-dimensional space inside electronics,posing a major obstacle to the integra-tion of electronics.The innovation of integrating 3D-printed conformal shielding(c-SE)modules with packaging materials onto core electronics offers infinite possibilities to satisfy ideal SE func-tion without occupying additional space.Herein,the 3D printable carbon-based inks with various proportions of graphene and carbon nanotube nanoparticles are well-formulated by manipulating their rheological peculiarity.Accordingly,the free-constructed architectures with arbitrarily-customized structure and multifunctionality are created via 3D printing.In particular,the SE performance of 3D-printed frame is up to 61.4 dB,simultaneously accompanied with an ultralight architecture of 0.076 g cm^(-3) and a superhigh specific shielding of 802.4 dB cm3 g^(-1).Moreover,as a proof-of-concept,the 3D-printed c-SE module is in situ integrated into core electronics,successfully replacing the traditional metal-based module to afford multiple functions for electromagnetic compatibility and thermal dissipa-tion.Thus,this scientific innovation completely makes up the blank for assembling carbon-based c-SE modules and sheds a brilliant light on developing the next generation of high-performance shielding materials with arbitrarily-customized structure for integrated electronics. 展开更多
关键词 3D printing Carbon-based nanoparticles Conformal electromagnetic interference shielding Integrated electronics
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Silencing of signal transducer and activator of transcription 3 expression by RNA interference suppresses growth of human hepatocellular carcinoma in tumor-bearing nude mice 被引量:13
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作者 Jing Li Yun-Feng Piao +2 位作者 Zheng Jiang Li Chen Hai-Bo Sun 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第21期2602-2608,共7页
AIM: To explore the effect of silencing of signal transducer and activator of transcription 3 (STAT3) expression by RNA interference (RNAi) on growth of human hepatocellular carcinoma (HCC) in tumorbearing nude... AIM: To explore the effect of silencing of signal transducer and activator of transcription 3 (STAT3) expression by RNA interference (RNAi) on growth of human hepatocellular carcinoma (HCC) in tumorbearing nude mice in vivo.METHODS: To construct the recombinant plasmid of pSilencer 3.0-H1-STAT3-siRNA-GFP (pSHI-siRNA- STAT3) and establish the tumor-bearing nude mouse model of the HCC cell line SMMC7721, we used intratumoral injection together with electroblotting to transfect the recombinant plasmid pSHI-siRNA- STAT3 into the transplanted tumor. The weight of the nude mice and tumor volumes were recorded. STAT3 gene transcription was detected by semi-quantitative reverse transcription polymerase chain reaction (RT- PCR). Level of protein expression and location of STAT3 were determined by Western blotting and immunohistochemical staining. STAT3-related genes such as survivin, c-myc, VEGF, p53 and caspase3 mRNA and protein expression were detected in tumor tissues at the same time. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay was used to detect apoptosis of tumor cells.RESULTS: The weight of the treated nude mice increased, and the tumor volume decreased markedly compared with those of the mock-treated and negative control groups (P 〈 0.01). The results of RT-PCR and Western blotting showed that mRNA and protein levels of STAT3 declined markedly in the treated group. The change in STAT3-related gene expression in tumor tissues at the mRNA and protein level also varied, the expression of survivin, VEGF and c-myc were obviously reduced, and expression of p53 and caspase3 increased (P 〈 0.01). Most of the tumor tissue ceils in the treated group developed apoptosis that was detected by TUNEL assay.CONCLUSION: Silencing of STAT3 expression by RNAi significantly inhibits expression of STAT3 mRNA and protein, and suppresses growth of human HCC in tumor-bearing nude mice. The mechanism may be related to down-regulation of survivin, VEGF and c-myc and up-regulation of p53 and caspase3 expression. Accordingly, the STAT3 gene may act as an important and effective target in gene therapy of HCC. 展开更多
关键词 RNA interference Signal transducerand activator of transcription 3 transcription factor Hepatocellular carcinoma Xenograft model antitumorassays Nude mouse
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Mechanically strong and folding-endurance Ti_(3)C_(2)T_(x)MXene/PBO nanofiber films for efficient electromagnetic interference shielding and thermal management 被引量:20
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作者 Lei Wang Zhonglei Ma +3 位作者 Yali Zhang Hua Qiu Kunpeng Ruan Junwei Gu 《Carbon Energy》 SCIE CAS 2022年第2期200-210,共11页
Electromagnetic interference(EMI)shielding materials with excellent flexibility and mechanical properties and outstanding thermal conductivity have become a hot topic of research in functional composites.In this study... Electromagnetic interference(EMI)shielding materials with excellent flexibility and mechanical properties and outstanding thermal conductivity have become a hot topic of research in functional composites.In this study,the“sol-gel-film conversion technique”is used to assemble polyetherimidefunctionalized Ti_(3)C_(2)T_(x)nanosheets(f-Ti_(3)C_(2)T_(x))with poly(p-phenylene-2,6-benzobisoxazole)(PBO)nanofibers(PNFs),followed by dialysis and vacuum drying to prepare f-Ti_(3)C_(2)T_(x)/PNF films with lamellar structures.When the loading of f-Ti_(3)C_(2)T_(x)is 70 wt%,the f-Ti_(3)C_(2)T_(x)/PNF film presents optimal comprehensive properties,with an EMI shielding effectiveness(SE)of 35 dB and a specific SE/thickness((SSE,SE/density)/t)of 8211 dB cm^(2)/g,a tensile strength of 125.1 MPa,an in-plane thermal conductivity coefficient(λ)of 5.82 W/(m K),and electrical conductivity of 1943 S/m.After repeated folding for 10,000 cycles,the EMI SE and the tensile strength of f-Ti_(3)C_(2)T_(x)/PNFs films still remain 33.4 dB and 116.1 MPa,respectively.Additionally,the f-Ti_(3)C_(2)T_(x)/PNF film also shows excellent thermal stability,flame retardancy,and structural stability.This would provide a novel method for the design and fabrication of multifunctional composite films and considerably expand the applications of MXene-and PNF-based composites in the fields of EMI shielding and thermal management. 展开更多
关键词 electromagnetic interference shielding PBO nanofibers thermal management Ti_(3)C_(2)T_(x)MXene
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Phosphoinositide-3-kinase,catalytic,alpha polypeptide RNA interference inhibits growth of colon cancer cell SW948 被引量:4
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作者 Wen-Sheng Huang Tian-Bao Wang +3 位作者 Yao He Yu-Jun Chen Shi-Long Zhong Min Tan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第26期3458-3464,共7页
AIM:To investigate the gene knock-down effect by the phosphoinositide-3-kinase,catalytic,alpha polypeptide(PIK3CA)-targeted double-stranded RNA(dsRNA) and its effect on cell proliferation and cycle distribution in SW9... AIM:To investigate the gene knock-down effect by the phosphoinositide-3-kinase,catalytic,alpha polypeptide(PIK3CA)-targeted double-stranded RNA(dsRNA) and its effect on cell proliferation and cycle distribution in SW948.METHODS:Two PIK3CA-targeted dsRNAs were constructed and transfected into SW948 cells.Transfections were performed using lipofectamine TM 2000.The transfection effectiveness was calculated basing on the rate of fluorescence cell of SW948 at 6 h after transfection.Total messenger RNA was extracted from these cells using the RNeasy kit,and semiquantitative reverse transcription polymerase chain reaction was performed to detect the down-regulation of PIK3CA,AKT1,MYC,and CCND1 gene expression.Cells were harvested,proteins were resolved,and western blot was employed to detect the expression levels of PIK3CA,AKT1,MYC,and CCND1 gene.Cell proliferation was assessed by 3-(4,5)-dimethylthiahiazo(-z-y1)-3,5-di-phenytetrazoliumromide assay and the inhibition rate was calculated.Soft agar colony formation assay was performed basing on colonies greater than 60 μm in diameter at ×100 magnification.The effect on cell cycle distribution and apoptosis was assessed by flow cytometry.All experiments were performed in triplicate.RESULTS:Green fluorescence was observed in SW948 cell transfected with plasmid Pgenesil-1,and the transfection effectiveness was about 65%.Forty-eight hours post-transfection,mRNA expression of PIK3CA in SW948 cells was 0.51 ± 0.04 vs 0.49 ± 0.03 vs 0.92 ± 0.01 vs 0.93 ± 0.03(P = 0.001) in Pgenesil-CA1,Pgenesil-CA2,negative and blank group respectively.mRNA expression of AKT1 was 0.50 ± 0.03 vs 0.48 ± 0.01 vs 0.93 ± 0.04 vs 0.92 ± 0.02(P = 0.000) in Pgenesil-CA1,Pgenesil-CA2,negative and blank group respectively.mRNA expression of MYC was 0.49 ± 0.01 vs 0.50 ± 0.04 vs 0.90 ± 0.02 vs 0.91 ± 0.03(P = 0.001) in the four groups respectively.mRNA expression of CCND1 was 0.45 ± 0.02 vs 0.51 ± 0.01 vs 0.96 ± 0.03 vs 0.98 ± 0.01(P = 0.001) in the four groups respectively.The protein level of PIK3CA was 0.53 ± 0.01 vs 0.54 ± 0.02 vs 0.92 ± 0.03 vs 0.91 ± 0.02(P = 0.001) in Pgenesil-CA1,Pgenesil-CA2,negative and blank group respectively.The protein level of AKT1 in the four groups was 0.49 ± 0.02 vs 0.55 ± 0.03 vs 0.94 ± 0.03 vs 0.95 ± 0.04,P = 0.000).The protein level of MYC in the four groups was 0.51 ± 0.03 vs 0.52 ± 0.04 vs 0.92 ± 0.02 vs 0.95 ± 0.01(P = 0.000).The protein level of CCND1 in the four groups was 0.54 ± 0.04 vs 0.56 ± 0.03 vs 0.93 ± 0.01 vs 0.93 ± 0.03(P = 0.000).Both Pgenesil-CA1 and Pgenesil-CA2 plasmids significantly suppressed the growth of SW948 cells when compared with the negative or blank group at 48 h after transfec-tion(29% vs 25% vs 17% vs 14%,P = 0.001),60 h after transfection(38% vs 34% vs 19% vs 16%,P = 0.001),and 72 h after transfection(53% vs 48% vs 20% vs 17%,P = 0.000).Numbers of colonies in negative,blank,CA1,and CA2 groups were 42 ± 4,45 ± 5,8 ± 2,and 10 ± 3,respectively(P = 0.000).There were more than 4.5 times colonies in the blank and negative control groups as there were in the CA1 and CA2 groups.In addition,the colonies in blank and negative control groups were also larger than those in the CA1 and CA2 groups.The percentage of cells in the CA1 and CA2 groups was significantly higher in G 0 /G 1 phase,but lower in S and G 2 /M phase when compared with the negative and control groups.Moreover,cell apoptosis rates in the CA1 and CA2 groups were 5.11 ± 0.32 and 4.73 ± 0.32,which were significantly higher than those in negative(0.95 ± 0.11,P = 0.000) and blank groups(0.86 ± 0.13,P = 0.001).No significant difference was found between CA1 and CA2 groups in cell cycle distribution and apoptosis.CONCLUSION:PIK3CA-targeted short hairpin RNAs can block the phosphoinositide 3-kinase-Akt signaling pathway and inhibit cell growth,increase apoptosis,and induce cell cycle arrest in the PIK3CA-mutant colon cancer SW948 cells. 展开更多
关键词 Phosphoinositide-3-kinase catalytic alphapolypeptide RNA interference Colon cancer Phos-phoinositide-3-kinase pathway
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Dielectric,Electromagnetic Interference Shielding and Absorption Properties of Si_3N_4-PyC Composite Ceramics 被引量:2
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作者 Xuan Hao Xiaowei Yin +1 位作者 Litong Zhang Laifei Cheng 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2013年第3期249-254,共6页
Pyrolytic carbon (PyC) was infiltrated into silicon nitride (Si3N4) ceramics by precursor infiltration and pyrolysis (PIP) of phenolic resin, and Ni nanoparticles were added into the phenolic resin to change the... Pyrolytic carbon (PyC) was infiltrated into silicon nitride (Si3N4) ceramics by precursor infiltration and pyrolysis (PIP) of phenolic resin, and Ni nanoparticles were added into the phenolic resin to change the electric conductivity of Si3N4-PyC composite ceramics. Dielectric permittivity, electromagnetic interference (EMI) shielding and absorption properties of Si3N4-PyC composite ceramics were studied as a function of Ni content at 8.2-12.4 GHz (X-band). When Ni nanoparticles were added into phenolic resin, the electric conductivity of the prepared composite ceramics decreased with increasing Ni content, which was attributed to the decrease of graphitization degree of PyC. The decrease in electric conductivity led to the decrease in both permittivity and EMI shielding effectiveness. Since too high permittivity is harmful to the impendence match and results in the strong reflection, the electromagnetic wave absorption property of Si3N4-PyC composite ceramics increases with increasing Ni content. When the content of Ni nanoparticles added into phenolic resin was 2 wt%, the composite ceramics possessed the lowest electric conductivity and displayed the most excellent absorption property with a minimum reflection loss as low as -28.9 dB. 展开更多
关键词 Si3N4-PyC Dielectric property Electromagnetic interference shielding effectiveness Reflection loss
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Effects of RNA Interference Combined with Ultrasonic Irradiation and SonoV ue Microbubbles on Expression of STAT3 Gene in Keratinocytes of Psoriatic Lesions 被引量:4
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作者 冉立伟 王昊 +2 位作者 兰东 贾红侠 于思思 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第2期279-285,共7页
The most effective sequence of small interfering RNA(si RNA) silencing STAT3 of psoriatic keratinocytes(KCs) was screened out,and the effects of the most effective si RNA combined with ultrasonic irradiation and S... The most effective sequence of small interfering RNA(si RNA) silencing STAT3 of psoriatic keratinocytes(KCs) was screened out,and the effects of the most effective si RNA combined with ultrasonic irradiation and Sono Vue microbubbles on the expression of STAT3 of KCs and the dose-and time-response were investigated.Three chemically-synthetic si RNAs targeting STAT3 carried by Lipofectamine 3000 were transfected into KCs,and the effects on STAT3 expression were detected,then the most effective si RNA was selected for the subsequent experiments.The negative controls of siR NA(si RNA-NC) labeled with Cy3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and Sono Vue microbubbles were transfected into KCs,then the optimal parameters of ultrasonic irradiation were determined.The most effective si RNA carried by Lipofectamine 3000 combined with ultrasonic irradiation at the optimal parameters and Sono Vue microbubbles was transfected into KCs,and the dose-and time-response of RNA interference was determined.The effect of RNA interference by the most effective si RNA at the optimal time and dose carried by Lipofectamine 3000 combined with ultrasonic irradiation and Sono Vue microbubbles(LUS group) was compared with that only carried by Lipofectamine 3000(L group).The results showed that si RNA-3 achieved the highest silencing efficacy.0.5 W/cm2 and 30 s were selected as the parameters of ultrasonic irradiation.The si RNA-3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and Sono Vue microbubbles could effectively knock down the STAT3 expression at m RNA and protein levels in dose-and time-dependent manners determined at 100 nmol/L with maximum downregulation on m RNA at 48 h,and on protein at 72 h after transfection.The LUS group achieved the highest silencing efficacy.It was concluded that si RNA-3 carried by Lipofectamine 3000 combined with ultrasonic irradiation and SonoV ue microbubbles could effectively knock down the STAT3 expression in psoriatic KCs,and the optimized transfection condition and the sequence of si RNA-3 could serve for further research on gene therapy of psoriasis. 展开更多
关键词 STAT3 keratinocytes psoriasis RNA interference small interfering RNA ultrasonic irradiation microbubbles expression
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Self-Interference Elimination by Physical Feedback Channel in CCFD for 3-D Beamforming Communication 被引量:2
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作者 Naveed Ali Kaimkhani Zhe Chen Fuliang Yin 《China Communications》 SCIE CSCD 2017年第9期62-71,共10页
The 3-D beamforming scheme has elite as evolving interest because of its efficiency to empower assorted techniques such as vertical and horizontal domains and emanation beamforming according to subscriber's provis... The 3-D beamforming scheme has elite as evolving interest because of its efficiency to empower assorted techniques such as vertical and horizontal domains and emanation beamforming according to subscriber's provisions. Usually, 3-D beamforming communication is set up on FDD/TDD approach those effects on the performance of spectrum and energy efficiency. Co-frequency and CoTime Full Duplex(CCFD) is an effective solution to improve the spectrum and energy efficiency by transmitting and receiving simultaneously in frequency and time domain. While, CCFD communication often face the self-interference issue when communication occurs, simultaneously. Consequently, in this paper a self-interference elimination by physical feedback channel in CCFD for 3-D Beamforming communication scheme is proposed to improve the over-all system performance in terms of energy and spectrum efficiency. The simulation and analytical outcomes demonstrated that the proposed system is superior than the traditional one. 展开更多
关键词 spectrum efficiency energy effi-ciency co-frequency and co-time full DUPLEX SELF-interference suppression 3-D beamform-ing
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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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Biomechanical and Biological Properties of Stereolithography-Based 3D-Printed Zirconia Interference Screws for Anterior Cruciate Ligament Reconstruction
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作者 Hui Li Yue Hu +6 位作者 Xiaopeng Tang Yun Zhao Mei Li Yixuan Zhao Hao Luo Qingguo Lai Hongyu Xing 《Additive Manufacturing Frontiers》 2024年第3期87-99,共13页
For effective anterior cruciate ligament(ACL)reconstruction,an interference screw(IFS)is employed to force transplantation of the ligament into the bone tunnel.In this study,IFSs were successfully designed and pre-par... For effective anterior cruciate ligament(ACL)reconstruction,an interference screw(IFS)is employed to force transplantation of the ligament into the bone tunnel.In this study,IFSs were successfully designed and pre-pared,and the top tooth width,thread depth,and drive structure were parameterized with a forming accuracy of 80.0±21.1μm using SLA-3D printing technology.To improve the initial stability of ACL reconstruction,a biomechanical model was established,and the results were optimized through insertion torque and tensile test-ing.Consequently,the IFS with the top tooth width of 0.4 mm,thread depth of 0.8 mm,and hexagon drive,matching with theΦ8 mm bone tunnel,exhibits the best mechanical properties(maximum insertion torque of 1.064±0.117 N m,ultimate load of 446.126±37.632 N,stiffness of 66.33±27.48 N/mm).Additionally,the ZrO_(2)/PDA/RGD/Zn^(2+)bioactive coating was found to significantly improve the surface bioactivity of zirconia IFS.In conclusion,this study has significant implications for ACL reconstruction. 展开更多
关键词 3D printing ZIRCONIA interference screw BIOMECHANICS Bioactive coating
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