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4天香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响
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作者 董晓飞 梁紫尧 +5 位作者 范龙 全景羽 林琳 周颖芳 吴蕾 于旭华 《中国免疫学杂志》 CAS CSCD 北大核心 2024年第1期67-71,共5页
目的:探讨短期香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响。方法:BALB/c小鼠随机分为4组:对照组、熏烟组、poly(I:C)组和熏烟联合poly(I:C)组。检测支气管肺泡灌洗液(BALF)中总细胞数及细胞分类计数;普通光镜... 目的:探讨短期香烟烟雾暴露联合poly(I:C)刺激对小鼠肺部免疫应答及干扰素表达的影响。方法:BALB/c小鼠随机分为4组:对照组、熏烟组、poly(I:C)组和熏烟联合poly(I:C)组。检测支气管肺泡灌洗液(BALF)中总细胞数及细胞分类计数;普通光镜下观察各组细胞形态;荧光定量PCR检测肺组织细胞因子、趋化因子和干扰素及干扰素刺激基因表达。结果:与对照组相比,熏烟联合poly(I:C)组总细胞数计数、巨噬细胞与中性粒细胞计数明显升高(P<0.05),且熏烟联合poly(I:C)组巨噬细胞计数高于poly(I:C)组;与poly(I:C)组比较,熏烟联合poly(I:C)组小鼠气道灌洗液巨噬细胞体积较大,呈圆形或不规则形,细胞质较多空泡;与对照组相比,熏烟联合poly(I:C)组小鼠肺组织中性粒细胞趋化因子CXCL1(P<0.05)、CXCL2(P<0.01)和淋巴细胞趋化因子CCL2(P<0.01)mRNA表达升高,肺组织IL-1β、IL-6、TNF-αmRNA表达明显升高(P<0.01),肺组织IFN-β(P<0.01)、IFN-γ(P<0.05)、MX2(P<0.01)和IP-10(P<0.01)表达显著升高,且与poly(I:C)组小鼠相比,熏烟联合poly(I:C)组小鼠肺组织CXCL2(P<0.05)、TNF-α(P<0.01)和IFN-β(P<0.05)mRNA表达明显升高。结论:熏烟联合poly(I:C)诱导了小鼠肺部炎症反应和干扰素及干扰素刺激基因表达。同时,香烟暴露加剧了poly(I:C)诱导的小鼠肺部急性炎症反应和Ⅰ型干扰素表达。 展开更多
关键词 香烟烟雾 poly(I:C) 免疫细胞 气道炎症 干扰素
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Innovative approach to boosting the chemical stability of AZ31 magnesium alloy using polymer-modified hybrid metal oxides
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作者 Mosab Kaseem Ananda Repycha Safira +3 位作者 Mohammad Aadil Tehseen Zehra Muhammad Ali Khan Arash Fattah-alhosseini 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第3期1068-1081,共14页
Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties.However,the integration of polymeric frameworks with MgO/WO_(3) composite l... Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties.However,the integration of polymeric frameworks with MgO/WO_(3) composite layers faces challenges due to the lack of understanding of the formation mechanism and the challenge of determining the impact of self-assembled architecture on anticorrosive properties.In this study,we aimed to enhance the corrosion resistance of the MgO layer produced by plasma electrolysis(PE)of AZ31 Mg alloy by incorporating WO_(3) with partially phosphorated poly(vinyl alcohol)(PPVA).Two types of porous MgO layers were produced using the PE process with an alkaline-phosphate electrolyte,one with and one without WO_(3) nanoparticles,which were subsequently immersed in an aqueous solution of PPVA.Incorporating PPVA into the WO_(3)-MgO layer resulted in hybrids being deposited in a fragmented manner,creating a“laminar reef-like structure”that sealed most of the structural defects in the layer.The PPVA-sealed WO_(3)-based coating exhibited superior corrosion resistance compared to the other samples.Computational analyses were employed to explore the mechanism underlying the formation of PPVA/WO_(3) hybrids on the MgO layer.These findings suggest that PPVA-WO_(3)-MgO hybrid coatings can potentially improve corrosion resistance in various fields. 展开更多
关键词 Plasma electrolysis poly(vinyl alcohol) Tungsten trioxide SEALING CORROSION DFT.
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TOPCon太阳电池背面叠层poly工艺的优化及其对电性能的影响
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作者 凡金星 刘绍洋 高纪凡 《太阳能》 2024年第4期73-79,共7页
通过增加TOPCon太阳电池poly层中的磷掺杂浓度可以增强poly层与硅基底之间的钝化效果并提高poly层与金属电极间的接触能力,但过高的掺杂浓度会导致磷原子扩散到硅基底,破坏氧化层与硅基底之间的界面钝化效果。为了解决这一问题,提出在p... 通过增加TOPCon太阳电池poly层中的磷掺杂浓度可以增强poly层与硅基底之间的钝化效果并提高poly层与金属电极间的接触能力,但过高的掺杂浓度会导致磷原子扩散到硅基底,破坏氧化层与硅基底之间的界面钝化效果。为了解决这一问题,提出在poly层中间增加一层薄的氧化层作为阻挡层(即叠层poly工艺,下文简称为“叠层工艺”)的方案,将原本单一的poly-Si磷掺杂进行双层分布,底层poly-Si轻掺杂,表层poly-Si重掺杂;对常规工艺和叠层工艺制备TOPCon的太阳电池进行对比试验后,进一步优化叠层工艺,调整中间氧化层厚度,并研究不同中间氧化层厚度的叠层工艺对TOPCon太阳电池电性能的影响。实验结果表明:1)叠层工艺可以提高TOPCon太阳电池的电性能;2)当中间氧化层厚度提升至1.5 nm时,太阳电池的光电转换效率达到最高值(25.66%)。但中间氧化层的厚度是一个需要精确控制的工艺参数,需找到最佳的厚度平衡点,以提高太阳电池性能。 展开更多
关键词 TOPCon太阳电池 poly 磷掺杂浓度 钝化效果
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Flexible and Robust Functionalized Boron Nitride/Poly(p‑Phenylene Benzobisoxazole)Nanocomposite Paper with High Thermal Conductivity and Outstanding Electrical Insulation
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作者 Lin Tang Kunpeng Ruan +3 位作者 Xi Liu Yusheng Tang Yali Zhang Junwei Gu 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期423-437,共15页
With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature... With the rapid development of 5G information technology,thermal conductivity/dissipation problems of highly integrated electronic devices and electrical equipment are becoming prominent.In this work,“high-temperature solid-phase&diazonium salt decomposition”method is carried out to prepare benzidine-functionalized boron nitride(m-BN).Subsequently,m-BN/poly(pphenylene benzobisoxazole)nanofiber(PNF)nanocomposite paper with nacremimetic layered structures is prepared via sol–gel film transformation approach.The obtained m-BN/PNF nanocomposite paper with 50 wt%m-BN presents excellent thermal conductivity,incredible electrical insulation,outstanding mechanical properties and thermal stability,due to the construction of extensive hydrogen bonds andπ–πinteractions between m-BN and PNF,and stable nacre-mimetic layered structures.Itsλ∥andλ_(⊥)are 9.68 and 0.84 W m^(-1)K^(-1),and the volume resistivity and breakdown strength are as high as 2.3×10^(15)Ωcm and 324.2 kV mm^(-1),respectively.Besides,it also presents extremely high tensile strength of 193.6 MPa and thermal decomposition temperature of 640°C,showing a broad application prospect in high-end thermal management fields such as electronic devices and electrical equipment. 展开更多
关键词 poly(p-phenylene-2 6-benzobisoxazole)nanofiber Boron nitride Thermal conductivity Electrical insulation
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A comparative study for petroleum removal capacities of the bacterial consortia entrapped in sodium alginate,sodium alginate/poly(vinyl alcohol),and bushnell haas agar
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作者 Sezen Bilen Ozyurek 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期705-715,共11页
The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different pol... The purpose of this study was to identify and compare the degradation efficiencies of free and entrapped bacterial consortia(Staphylococcus capitis CP053957.1 and Achromobacter marplatensis MT078618.1)to different polymers such as Sodium Alginate(SA),Sodium Alginate/Poly(Vinyl Alcohol)(SA/PVA),and Bushnell Haas Agar(BHA).In addition to SA and SA/PVA,which are cost-effective,non-toxic and have different functional groups,BHA,which is frequently encountered in laboratory-scale studies but has not been used as an entrapment material until now.Based on these,the polymers with different surface morphologies and chemical compositions were analyzed by SEM and FT-IR.While the petroleum removal efficiency was higher with the entrapped bacterial consortia than with the free one,BHA-entrapped bacterial consortium enhanced the petroleum removal more than SA and SA/PVA.Accordingly,the degradation rate of bacterial consortia entrapped with BHA was 2.039 day^(-1),SA/PVA was 1.560,SA was 0.993,the half-life period of BHA-entrapped bacterial consortia is quite low(t_(1/2)=0.339)compared with SA(t_(1/2)=0.444)and SA/PVA(t_(1/2)=0.697).The effects of the four main factors such as:amount of BHA(0.5,1,1.5,2,2.5,3 g),disc size(4,5,6,7,8 mm),inoculum concentration(1,2.5,5,7.5,10 mL),and incubation period on petroleum removal were also investigated.The maximum petroleum removal(94.5%)was obtained at≥2.5 mL of bacterial consortium entrapped in 2 g BHA with a 7 mm disc size at 168 h and the results were also confirmed by statistical analysis.Although a decrease was observed during the reuse of bacterial consortium entrapped in BHA,the petroleum removal was still above 50%at 10th cycle.Based on GC-MS analysis,the removal capacity of BHA-entrapped consortium was over 90%for short-chain n-alkanes and 80%for medium-chain n-alkanes.Overall,the obtained data are expected to provide a potential guideline in cleaning up the large-scale oil pollution in the future.Since there has been no similar study investigating petroleum removal with the bacterial consortia entrapped with BHA,this novel entrapment material can potentially be used in the treatment of petroleum pollution in advanced remediation studies. 展开更多
关键词 Entrapment of bacterial consortia PETROLEUM RemovalBushnell Haas agar Sodium alginate Sodium alginate/poly(vinyl alcohol)
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High-performance and robust high-temperature polymer electrolyte membranes with moderate microphase separation by implementation of terphenyl-based polymers
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作者 Jinyuan Li Congrong Yang +3 位作者 Haojiang Lin Jicai Huang Suli Wang Gongquan Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期572-578,共7页
Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(te... Acid loss and plasticization of phosphoric acid(PA)-doped high-temperature polymer electrolyte membranes(HT-PEMs)are critical limitations to their practical application in fuel cells.To overcome these barriers,poly(terphenyl piperidinium)s constructed from the m-and p-isomers of terphenyl were synthesized to regulate the microstructure of the membrane.Highly rigid p-terphenyl units prompt the formation of moderate PA aggregates,where the ion-pair interaction between piperidinium and biphosphate is reinforced,leading to a reduction in the plasticizing effect.As a result,there are trade-offs between the proton conductivity,mechanical strength,and PA retention of the membranes with varied m/p-isomer ratios.The designed PA-doped PTP-20m membrane exhibits superior ionic conductivity,good mechanical strength,and excellent PA retention over a wide range of temperature(80–160°C)as well as satisfactory resistance to harsh accelerated aging tests.As a result,the membrane presents a desirable combination of performance(1.462 W cm^(-2) under the H_(2)/O_(2)condition,which is 1.5 times higher than that of PBI-based membrane)and durability(300 h at 160°C and 0.2 A cm^(-2))in the fuel cell.The results of this study provide new insights that will guide molecular design from the perspective of microstructure to improve the performance and robustness of HT-PEMs. 展开更多
关键词 Fuel cell High-temperature polymer electrolyte membranes Microphase separation poly(terphenyl piperidinium)s Phosphoric acid
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Edaravone-loaded poly(amino acid) nanogel inhibits ferroptosis for neuroprotection in cerebral ischemia injury
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作者 Yunhan Zhang Zhulin Zou +5 位作者 Shuang Liu Fangfang Chen Minglu Li Haoyang Zou Haiyan Liu Jianxun Ding 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第2期89-101,共13页
Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulat... Neurological injury caused by ischemic stroke is a major cause of permanent disability and death. The currently available neuroprotective drugs fail to achieve desired therapeutic efficacy mainly due to short circulation half-life and poor blood−brain barrier (BBB) permeability. For that, an edaravone-loaded pH/glutathione (pH/GSH) dual-responsive poly(amino acid) nanogel (NG/EDA) was developed to improve the neuroprotection of EDA. The nanogel was triggered by acidic and EDA-induced high-level GSH microenvironments, which enabled the selective and sustained release of EDA at the site of ischemic injury. NG/EDA exhibited a uniform sub-spherical morphology with a mean hydrodynamic diameter of 112.3 ± 8.2 nm. NG/EDA efficiently accumulated at the cerebral ischemic injury site of permanent middle cerebral artery occlusion (pMCAO) mice, showing an efficient BBB crossing feature. Notably, NG/EDA with 50 µM EDA significantly increased neuron survival (29.3%) following oxygen and glucose deprivation by inhibiting ferroptosis. In addition, administering NG/EDA for 7 d significantly reduced infarct volume to 22.2% ± 7.2% and decreased neurobehavioral scores from 9.0 ± 0.6 to 2.0 ± 0.8. Such a pH/GSH dual-responsive nanoplatform might provide a unique and promising modality for neuroprotection in ischemic stroke and other central nervous system diseases. 展开更多
关键词 poly(amino acid)nanogel Controlled drug delivery Inhibition of ferroptosis NEUROPROTECTION Cerebral ischenia injury therapy
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Systematic analysis of DNA polymerases as therapeutic targets in pan-cancers
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作者 ZHENHUA LI HUILAI LV +8 位作者 FAN ZHANG ZIMING ZHU QIANG GUO MINGBO WANG CHAO HUANG LIJUAN CHEN WENPAN ZHANG YUN LI ZIQIANG TIAN 《BIOCELL》 SCIE 2024年第1期123-138,共16页
Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy ... Introduction:DNA polymerases are crucial for maintaining genome stability and influencing tumorigenesis.However,the clinical implications of DNA polymerases in tumorigenesis and their potential as anti-cancer therapy targets are not well understood.Methods:We conducted a systematic analysis using TCGA Pan-Cancer Atlas data and Gene Set Cancer Analysis results to examine the expression profiles of 15 DNA polymerases(POLYs)and their clinical correlations.We also evaluated the prognostic value of POLYs by analyzing their expression levels in relation to overall survival time(OS)using Kaplan-Meier survival curves.Additionally,we investigated the correlations between POLY expression and immune cells,DNA damage repair(DDR)pathways,and ubiquitination.Drug sensitivity analysis was performed to assess the relationship between POLY expression and drug response.Results:Our analysis revealed that 14 out of 15 POLYs exhibited significantly distinct expression patterns between tumor and normal samples across most cancer types,except for DNA nucleotidylexotransferase(DNTT).Specifically,POLD1 and POLE showed elevated expression in almost all cancers,while POLQ exhibited high expression levels in all cancer types.Some POLYs showed heightened expression in specific cancer subtypes,while others exhibited low expression.Kaplan-Meier survival curves demonstrated significant prognostic value of POLYs in multiple cancers,including PAAD,KIRC,and ACC.Cox analysis further validated these findings.Alteration patterns of POLYs varied significantly among different cancer types and were associated with poorer survival outcomes.Significant correlations were observed between the expression of POLY members and immune cells,DDR pathways,and ubiquitination.Drug sensitivity analysis indicated an inverse relationship between POLY expression and drug response.Conclusion:Our comprehensive study highlights the significant role of POLYs in cancer development and identifies them as promising prognostic and immunological biomarkers for various cancer types.Additionally,targeting POLYs therapeutically holds promise for tumor immunotherapy. 展开更多
关键词 DNA polymerases(polys) Prognostic biomarker The Cancer Genome Atlas(TCGA) Ubiquitination network
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Application of the Shrinking Particle Model for the Evaluation of Molecular Recyclability of PET versus Semi-Aromatic Polyesters
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作者 Jack van Schijndel Sanne de Krom +2 位作者 Dennis Molendijk Koen van Beurden Amarante Böttger 《Open Journal of Physical Chemistry》 2024年第2期21-35,共15页
The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is e... The molecular recyclability of poly (ethylene terephthalate) (PET) and three semi-aromatic polyesters poly (phloretic acid) (poly-H), poly (dihydroferulic acid) (poly-G), and poly (dihydrosinapinic acid) (poly-S) is evaluated in this study. PET is an extensively used aromatic polyester, and poly-H, poly-G, and poly-S can be considered semi-aromatic poly (lactic acid) modifications. All these polyesters have been depolymerized at neutral pH and by acid- and base-catalyzed hydrolysis at two temperatures, i.e., 50˚C and 80˚C. Base-catalyzed depolymerization of virgin PET leads to an isolated yield of 38% after 48 hours of reaction at 80˚C. Contrary to these results for PET, almost all the monomers of the semi-aromatic polyesters poly-H, poly-G, and poly-S are recovered with isolated yields larger than 90% at the same temperature after 15 minutes in a facile manner. A shrinking particle model used to determine the global kinetics of the base-catalyzed depolymerization showed that the rate rises with increasing temperature. Using the shrinking particle model, the intrinsic reaction rate constants were determined. It has been demonstrated that the rate coefficients of the depolymerization of the semi-aromatic polyesters poly-H, poly-G, and poly-S are between 2 and 3 orders of magnitude higher than those for PET. 展开更多
关键词 DEpolyMERIZATION Molecular Recycling poly-H poly-G poly-S PET Circular polymers
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Novel sandwich structured glass fiber Cloth/Poly(ethylene oxide)-MXene composite electrolyte
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作者 Yu-Qin Mao Guang-He Dong +3 位作者 Wei-Bin Zhu Yuan-Qing Li Pei Huang Shao-Yun Fu 《Nano Materials Science》 EI CAS CSCD 2024年第1期60-67,共8页
Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performa... Recently,poly(ethylene oxide)(PEO)-based solid polymer electrolytes have been attracting great attention,and efforts are currently underway to develop PEO-based composite electrolytes for next generation high performance all-solid-state lithium metal batteries.In this article,a novel sandwich structured solid-state PEO composite electrolyte is developed for high performance all-solid-state lithium metal batteries.The PEO-based composite electrolyte is fabricated by hot-pressing PEO,LiTFSI and Ti_(3)C_(2)T_(x) MXene nanosheets into glass fiber cloth(GFC).The as-prepared GFC@PEO-MXene electrolyte shows high mechanical properties,good electrochemical stability,and high lithium-ion migration number,which indicates an obvious synergistic effect from the microscale GFC and the nanoscale MXene.Such as,the GFC@PEO-1 wt%MXene electrolyte shows a high tensile strength of 43.43 MPa and an impressive Young's modulus of 496 MPa,which are increased by 1205%and 6048%over those of PEO.Meanwhile,the ionic conductivity of GFC@PEO-1 wt%MXene at 60℃ reaches 5.01×10^(-2) S m^(-1),which is increased by around 200%compared with that of GFC@PEO electrolyte.In addition,the Li/Li symmetric battery based on GFC@PEO-1 wt%MXene electrolyte shows an excellent cycling stability over 800 h(0.3 mA cm^(-2),0.3 mAh cm^(-2)),which is obviously longer than that based on PEO and GFC@PEO electrolytes due to the better compatibility of GFC@PEO-1 wt%MXene electrolyte with Li anode.Furthermore,the solid-state Li/LiFePO_(4) battery with GFC@PEO-1 wt%MXene as electrolyte demonstrates a high capacity of 110.2–166.1 mAh g^(-1) in a wide temperature range of 25–60C,and an excellent capacity retention rate.The developed sandwich structured GFC@PEO-1 wt%MXene electrolyte with the excellent overall performance is promising for next generation high performance all-solid-state lithium metal batteries. 展开更多
关键词 Solid polymer electrolyte Ti_(3)C_(2)T_(x)MXene poly(ethylene oxide) Glass fiber cloth All-solid-state Li metal Battery
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TOPCon太阳电池单面沉积Poly-Si的工艺研究
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作者 代同光 谭新 +4 位作者 宋志成 郭永刚 袁雅静 倪玉凤 汪梁 《人工晶体学报》 CAS 北大核心 2024年第5期818-823,共6页
目前隧穿氧化层钝化接触(TOPCon)电池制造技术越来越成熟,所耗成本不断降低。行业内普遍采用低压化学气相沉积(LPCVD)方式进行双面沉积或单面沉积。单面沉积存在Poly-Si绕镀问题,严重影响电池片转化效率和外观质量,同时正面绕镀层去除... 目前隧穿氧化层钝化接触(TOPCon)电池制造技术越来越成熟,所耗成本不断降低。行业内普遍采用低压化学气相沉积(LPCVD)方式进行双面沉积或单面沉积。单面沉积存在Poly-Si绕镀问题,严重影响电池片转化效率和外观质量,同时正面绕镀层去除难度较大,在用碱溶液去除绕镀层的同时,存在绕镀层去除不彻底或者非绕镀区域P^(+)层被腐蚀的风险,导致P^(+)发射极受损,严重影响电池片外观质量与性能。双面沉积可避免上述问题,但产能减少一半,制造成本增加。本文对单面沉积Poly-Si工艺及绕镀层去除工艺进行研究,在TOPCon电池正面及背面制作了一层合适厚度的氧化层掩膜,搭配合适的清洗工艺、去绕镀清洗工艺,既可有效地去除P^(+)层绕镀的Poly-Si,也可很好地保护正面P^(+)层及背面掺杂Poly-Si层不受破坏,同时可大幅提升产能。 展开更多
关键词 TOPCon太阳电池 poly-Si绕镀层 低压化学气相沉积 BSG PSG 腐蚀速率
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Catalytic Hydrogenation over Palladium Complex of Molecular Complex of Poly(4-vinylpyridine) with Acetic Acid 被引量:1
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作者 XI Xiang li ZHU Jing CAO Shao kui 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期76-79,共4页
The palladium complex of the molecular complex of poly(4 vinylpyridine) with acetic acid(PVP/ HAc Pd) was prepared. Its catalytic activity for the hydrogenation of nitrobenzene was found much higher than that of the c... The palladium complex of the molecular complex of poly(4 vinylpyridine) with acetic acid(PVP/ HAc Pd) was prepared. Its catalytic activity for the hydrogenation of nitrobenzene was found much higher than that of the corresponding palladium complex of poly(4 vinylpyridine). In the presence of a strong inorganic alkali, especially potassium hydroxide, the catalytic activity is greatly improved. The suitable hydrogenation condition for PVP/HAc Pd is to use 0 1 mol/L ethanol solution of potassium hydroxide as the hydrogenation medium and the hydrogenation is carried out at 45 ℃. 展开更多
关键词 Palladium catalyst HYDROGENATION Molecular complex NITROBENZENE poly(4-vinylpyridine) Acetic acid
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Features of Polymethacrylic Acid and Poly-2-Methyl-5-Vinylpyridine Hydrogels Remote Interaction in an Aqueous Medium 被引量:1
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作者 Alimbekova Bagyla Talgatovna Korganbayeva Zhanar Kozhamberdikyzy Himersen Huangul Kondaurov Ruslan Gennadievich Jumadilov Talkybek Kozhataevich 《Journal of Chemistry and Chemical Engineering》 2014年第3期265-269,共5页
关键词 聚甲基丙烯酸 乙烯基吡啶 水凝胶 远程 水介质 特征 交互 相互作用
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Electrocatalytic Activity of Platinum Particles Electrodeposited onto Poly(vinylpyridine) Films
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作者 LinNIU FengHuaWEI 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第11期1119-1120,共2页
The electrocatalytic properties of platinum microparticles incorporated into poly-(vinylpyridine) (PVP) films, a conducting polymer with good conductivity and stability, were investigated for hydrogen evolution and fo... The electrocatalytic properties of platinum microparticles incorporated into poly-(vinylpyridine) (PVP) films, a conducting polymer with good conductivity and stability, were investigated for hydrogen evolution and formic acid electrooxidation in acidic media. It wasfound that the catalytic effects depend mainly on the size and amounts of the platinummicroparticles dispersed in the polymer layer. 展开更多
关键词 ELECTROCATALYSIS PLATINUM poly(vinylpyridine) formic acid hydrogen.
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Research on poly(styrene-acrylic acid)-supported neodymium complex in catalytic copolymerization of styrene and 4-vinylpyridine 被引量:2
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作者 陈瑞战 李晓莉 +2 位作者 王晓菊 张永宏 赵伦 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期326-330,共5页
The catalytic activity of poly(styrene-acrylic acid) (PSAA) supported neodymium chloride (NdCl3) complex for the copolymerization of styrene and 4-Vinylpyridine was studied. The influence of various factors, suc... The catalytic activity of poly(styrene-acrylic acid) (PSAA) supported neodymium chloride (NdCl3) complex for the copolymerization of styrene and 4-Vinylpyridine was studied. The influence of various factors, such as Al/Nd molar ratio, reaction time, macromolecular carder (PSAA), and ratio of styrene to 4-vinypyridine (g/g), on the copolymerization yield of styrene and 4-Vinylpyridine was investigated. The results showed that the copolymerization of polar monomers with olefins occurred efficiently and the catalytic activity of polymer-supported catalyst was higher than that of the similar small molecular catalysts. The activity of PSAA.Nd complex increased with in- creasing Al/Nd molar ratios and decreased with increasing polymerization time. The highest activity of PSAA'Nd was observed at 120 min, and the highest yield was found at the ratio of styrene to 4-vinylpyridine of 4:2. DSC analysis presented that the resulted polymer had only one glass transition temperature, and showed very good thermal stability. 展开更多
关键词 rare earth catalyst STYRENE 4-vinylpyridine polar monomer COpolyMERIZATION rare earths
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Study on Polymerization of 4-Vinylpyridine by Neodymium Complex Catalyst 被引量:1
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作者 王晓菊 陈瑞战 曲雅焕 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第2期155-157,共3页
Polymerization of 4-vinylpyridine by complex catalyst of neodymium chloride was studied. The influence of Al/Nd (molar ratio), concentration of catalyst, reaction time and temperature on polymerization of 4-vinylpyrid... Polymerization of 4-vinylpyridine by complex catalyst of neodymium chloride was studied. The influence of Al/Nd (molar ratio), concentration of catalyst, reaction time and temperature on polymerization of 4-vinylpyridine was investigated. The results show that different kinds of ligand in the rare earth complex have an effect on the catalytic activity of the complex. The catalytic activity of the rare earth complex is higher than that of simple rare earth chloride. The catalytic activity of polymer-supported catalyst is higher than those of the similar small molecular system. 展开更多
关键词 rare earths 4-vinylpyridine neodymium complex CATALYST polyMERIZATION
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PREPARATION OF NOVEL POLYETHYLENE-graft-POLY(4-VINYLPYRIDINE)-SUPPORTED METALLOCENE CATALYSTS FOR ETHYLENE POLYMERIZATION 被引量:2
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作者 孙文华 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第5期557-562,共6页
Polyethylene (PE) grafting 4-vinylpyridine copolymers has been produced as powders of different rushes by theirradiation method. After treatment with methylaluminoxane (MAO), the copolymers were used as supports for C... Polyethylene (PE) grafting 4-vinylpyridine copolymers has been produced as powders of different rushes by theirradiation method. After treatment with methylaluminoxane (MAO), the copolymers were used as supports for Cp_2ZrCl_2catalyst Results of X-ray photoelectron spectroscopy, Fourier transforms infrared spectroscopy, ultraviolet spectroscopy andscanning electron microscope measurements show that the catalytic sites have been linked through MAO on the PE-graft-4-vinylpyridine (PEVP). The percentages of grafting 4-vinylpyridine and supported Cp_2ZrCl_2 depend on the size ofpolyethylene powder. The smaller the polyethylene powder, the more percent of 4-vinylpyridine groups and Cp_2ZrCl_2 existon the polyethylene chains, and the PEVP-supported catalyst has a relatively high activity for ethylene polymerization. 展开更多
关键词 polyethylene grafting 4-vinylpyridine COpolyMER IRRADIATION Supported catalyst Cp_2ZrCl_2 Ethylene polymerization
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Fabrication of Poly(4-vinylpyridine) Nanofiber and Fluorescent Poly(4-vinylpyridine)/Porphyrin Nanofiber by Electrospinning
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作者 SONG Yan ZHAN Nai-qian +4 位作者 YU Miao YANG Qing-biao ZHANG Chao-qun WANG Heng-guo LI Yao-xian 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期722-725,共4页
Poly(4-vinylpyridine)(P4-VP) nanofiber and fluoresent poly(4-vinylpyridine)/porphyrin(P4-VP/TPPA) nanofiber were respectively prepared by electrospinning. The effect of the concentration of P4-VP/dimethylforma... Poly(4-vinylpyridine)(P4-VP) nanofiber and fluoresent poly(4-vinylpyridine)/porphyrin(P4-VP/TPPA) nanofiber were respectively prepared by electrospinning. The effect of the concentration of P4-VP/dimethylformamide (DMF) electrospinning solutions on the morphology of P4-VP nanofiber was investigated and it was found that the average diameter of the nanofiber of P4-VP/DMF increased with the increase of the concentration of the spinning solution. After the addition of TPPA to the P4-VP/DMF spinning solution, the diameter of P4-VP/TPPA nanofiber became even due to the increase of the conductivity of the P4-VP/DMF-TPPA solution. The photoluminescent(PL) spectral analysis indicates that the emission peak position of P4-VP/TPPA nanofiber is almost the same as that of pure TPPA at about 650 nm without peak shift, and when it was stored for 20 days, the emission peak of P4-VP/TPPA nanofiber is also at 650 nm, indicating that the fluorescent property of P4-VP/TPPA nanofiber is stable. Fourier-transform iufrared(FTIR) spectrum confirms the chemical composition of the resulting P4-VP/TPPA composite nanofiber. 展开更多
关键词 poly(4-vinylpyridine PORPHYRIN NANOFIBER ELECTROSPINNING
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Polymerization of 4-Vinylpyridine by Lanthanide Coordination Catalyst
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作者 Guo Hua TAN Yi Feng ZHANG +1 位作者 Zhi Guo HU Zhi Quan SHEN 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第7期681-682,共2页
Polymerization of 4-vinylpyridine was carried out with the lanthanide coordination catalyst. The influence of the component in catalytic system and solvents had been examined. The molecular weight of poly(4-vinylpyr... Polymerization of 4-vinylpyridine was carried out with the lanthanide coordination catalyst. The influence of the component in catalytic system and solvents had been examined. The molecular weight of poly(4-vinylpyridine) obtained in CH2Cl2 with Ln(P204)3 /Al(i-Bu)3 is more than 20104. 展开更多
关键词 vinylpyridine rare earth coordination catalyst polymerization.
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SYNTHESIS AND CHARACTERIZATION OF POLY(STYRENE-co-4-VINYLPYRIDINE) NEODYMIUM COMPLEX
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作者 李晓莉 于广谦 +2 位作者 李玉良 曲雅焕 苏树贵 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第2期185-189,共5页
Poly(styrene-co-4-vinylpyridine)-neodymium complexes(NdCl_3·PS4VPY)with variouscontents of the functional group and neodymium have been prepared and characterized.Theinfrared and X-ray photoelectron spectra indic... Poly(styrene-co-4-vinylpyridine)-neodymium complexes(NdCl_3·PS4VPY)with variouscontents of the functional group and neodymium have been prepared and characterized.Theinfrared and X-ray photoelectron spectra indicate that uncoordinated 4-vinylpyridine(4VPY)unitsremain in the NdCl_3·PS4VPY complexes.The catalytic behaviour of NdCl_3·PS4VPY was described briefly. 展开更多
关键词 poly(styrene-4-vinylpyridine) Neodymium complex Infrared spectra X-ray photoelectron spectra Catalytic behaviour
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