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Dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction for selective glucose photoreforming with remarkable H_(2)coproduction 被引量:1
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作者 Fuyan Kang Cai Shi +7 位作者 Yeling Zhu Malin Eqi Junming Shi Min Teng Zhanhua Huang Chuanling Si Feng Jiang Jinguang Hu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期158-167,共10页
The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a ... The global commitment to pivoting to sustainable energy and products calls for technology development to utilize solar energy for hydrogen(H_(2))and value-added chemicals production by biomass photoreforming.Herein,a novel dual-functional marigold-like Zn_(x)Cd_(1-x)S homojunction has been the production of lactic acid with high-yield and H_(2)with high-efficiency by selective glucose photoreforming.The optimized Zn_(0.3)Cd_(0.7)S exhibits outstanding H_(2)generation(13.64 mmol h^(-1)g^(-1)),glucose conversion(96.40%),and lactic acid yield(76.80%),over 272.80 and 19.21 times higher than that of bare ZnS(0.05 mmol h^(-1)g^(-1))and CdS(0.71 mmol h^(-1)g^(-1))in H_(2)generation,respectively.The marigold-like morphology provides abundant active sites and sufficient substrates accessibility for the photocatalyst,while the specific role of the homojunction formed by hexagonal wurtzite(WZ)and cubic zinc blende(ZB)in photoreforming biomass has been demonstrated by density functional theory(DFT)calculations.Glucose is converted to lactic acid on the WZ surface of Zn_(0.3)Cd_(0.7)S via the photoactive species·O_(2)^(-),while the H_(2)is evolved from protons(H^(+))in H_(2)O on the ZB surface of Zn_(0.3)Cd_(0.7)S.This work paves a promising road for the production of sustainable energy and products by integrating photocatalysis and biorefine. 展开更多
关键词 Zn_(x)Cd_(1-x)S homojunction selective glucose photoreforming Biomass valorization Sustainable H_(2) Photoreforming mechanism
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Selective hydrogenolysis of biomass-derived furfuryl alcohol into 1,2- and 1,5-pentanediol over highly dispersed Cu-Al_2O_3 catalysts 被引量:12
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作者 刘海龙 黄志威 +2 位作者 康海笑 夏春谷 陈静 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第5期700-710,共11页
Cu nanoparticles supported on a variety of oxide supports, including SiO2, TiO2, ZrO2, Al2O3, MgO and ZnO, were investigated for the hydrogenolysis of biomass‐derived furfuryl alcohol to1,2‐pentanediol and 1,5‐pent... Cu nanoparticles supported on a variety of oxide supports, including SiO2, TiO2, ZrO2, Al2O3, MgO and ZnO, were investigated for the hydrogenolysis of biomass‐derived furfuryl alcohol to1,2‐pentanediol and 1,5‐pentanediol. A Cu‐Al2O3 catalyst with 10 wt% Cu loading prepared by a co‐precipitation method exhibited the best performance in terms of producing pentanediols compared with the other materials. This catalyst generated an 85.8% conversion and a 70.3% combined selectivity for the target pentanediols at 413 K and 8 MPa H2 over an 8‐h reaction. The catalyst could also be recycled over repeated reaction trials without any significant decrease in productivity. Characterizations with X‐ray diffraction, NH3/CO2‐temperature programmed desorption, N2 adsorption,transmission electron microscopy and N2 O chemisorption demonstrated that intimate and effective interactions between Cu particles and the acidic Al2O3 support in this material greatly enhanced its activity and selectivity. The promotion of the hydrogenolysis reaction was found to be especially sensitive to the Cu particle size, and the catalyst with Cu particles 1.9 to 2.4 nm in size showed the highest turnover frequency during the synthesis of pentanediols. 展开更多
关键词 Furfuryl alcohol 1 2-Pentanediol 1 5-Pentanediol selective hydrogenolysis Cu-Al catalyst
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气肿疽梭菌C54-1株的制备与检定
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作者 任小侠 冯妍 +6 位作者 马欣 刘燕 王团结 杜吉革 潘晨帆 刘世博 张一帜 《中国兽药杂志》 2024年第2期10-17,共8页
为研究气肿疽梭菌C54-1株(CVCC60001)的菌种特性,制备了1批气肿疽梭菌C54-1株,并对菌种的形态及生化特性、培养特性、血清学特性、真空度、纯粹、剩余水分、毒力及免疫原性、16S rDNA等进行检定,以及对于该菌的适宜培养基促生长能力等... 为研究气肿疽梭菌C54-1株(CVCC60001)的菌种特性,制备了1批气肿疽梭菌C54-1株,并对菌种的形态及生化特性、培养特性、血清学特性、真空度、纯粹、剩余水分、毒力及免疫原性、16S rDNA等进行检定,以及对于该菌的适宜培养基促生长能力等方面进行了比较。实验结果表明,该冻干菌种的形态及生化特性、培养特性、血清学特性、真空度、纯粹、剩余水分、毒力及免疫原性均符合《中华人民共和国兽用生物制品规程》二〇〇〇版质量标准的规定。16S rDNA鉴定为气肿疽梭菌,相似度为99.93%。在免疫原性检定中,使用致死剂量攻毒时,免疫组能够4/4被保护,证明该菌明矾苗免疫效果良好。使用商品化梭菌培养基对于该菌培养进行了比对,证实商品化培养基替代厌气肉肝汤的可能性。本研究为气肿疽梭菌的制备和检定提供参考依据,并使用不同培养基进行比对研究,为该菌的稳定培养和疫苗工艺改进提供了研究基础。 展开更多
关键词 气肿疽梭菌C54-1 CVCC60001 毒力 免疫原性 培养基筛选 强化梭菌培养基(RCM) 苏木精-伊红染色法
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GLP-1受体激动剂药品评价体系构建与遴选实践
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作者 李烨 曹玮 《药品评价》 CAS 2024年第2期134-138,共5页
目的 基于《中国医疗机构药品评价与遴选快速指南(第二版)》(以下简称《快速指南》),对GLP-1受体激动剂进行综合评价,提高医院药事服务质量,为医院开展药品临床综合评价与遴选工作建立标准、合适、规范的参考依据和工作指导。方法 参考... 目的 基于《中国医疗机构药品评价与遴选快速指南(第二版)》(以下简称《快速指南》),对GLP-1受体激动剂进行综合评价,提高医院药事服务质量,为医院开展药品临床综合评价与遴选工作建立标准、合适、规范的参考依据和工作指导。方法 参考《快速指南》,从临床属性(有效性和安全性)、药学特性、经济性、其他属性4个维度对纳入的药品进行赋分,制定出符合医院实际的药品临床综合评价体系,开展评价并记录评价结果。结果 司美格鲁肽77.4分、利拉鲁肽76.6分、度拉糖肽73.9分、聚乙二醇洛塞那肽72.7分、利司那肽69.4分、艾塞那肽67.8分、贝那鲁肽65.5分。司美格鲁肽、利拉鲁肽、度拉糖肽、聚乙二醇洛塞那肽为强推荐,利司那肽、艾塞那肽、贝那鲁肽为弱推荐。结论 GLP-1受体激动剂是合并心血管疾病高危因素的糖尿病患者一线降糖药物之一,不同GLP-1受体激动剂在临床治疗中有不同的优势。通过《快速指南》对GLP-1受体激动剂进行遴选评价,可为医疗机构药品遴选与合理用药提供科学的参考依据。 展开更多
关键词 GLP-1受体激动剂 药品评价体系 药品遴选实践
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La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂对NO选择性生成NH_(3)的影响
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作者 宋崇林 郑庆贺 +3 位作者 吕誉 崔立峰 李云强 吕刚 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2024年第10期1053-1061,共9页
为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技... 为了实现碳中和目标,降低内燃机碳排放,稀薄燃烧技术成为了当前重要的研究方向.该技术不仅能提高发动机燃油热效率,还能有效降低CO_(2)排放.但是稀薄燃烧往往会伴随着大量氮氧化物的产生,为了解决该问题,采用LNT-SCR耦合的NO_(x)净化技术,此时LNT的作用是将排气中部分NO_(x)转化为NH_(3),为下游的SCR提供还原剂.基于此,制备了LNT催化剂,研究催化剂对NO选择性生成NH_(3)的影响.采用溶胶-凝胶法制备了La_(1-x)Ce_(x)MnO_(3)系列钙钛矿氧化物,并通过分步浸渍法得到了La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)负载型催化剂.利用XRD、H_(2)-TPR、NO-TPD等表征手段研究了钙钛矿氧化物的晶相结构,以及负载型催化剂的还原特性、NO_(x)吸附-脱附性能等物化性质,并且通过H_(2)选择性催化还原NO实验探究了催化剂掺杂Ce对NO转化成NH_(3)的影响.结果表明,Ce掺杂催化剂具有良好的NH_(3)产物选择性,并且显著提高了NO转化率.温度是NO转化和NH_(3)产物选择性生成的决定性因素,而H_(2)和NO体积比是NO转化和NH_(3)产物选择性生成的关键性因素.其中,La_(0.95)Ce_(0.05)MnO_(3)-Ba/Al_(2)O_(3)在低温下催化活性表现最佳,在350℃、H_(2)和NO体积比为5.0时NH_(3)产物选择性为65%,NO转化率为100%.此外,所制备的La_(1-x)Ce_(x)MnO_(3)都形成了钙钛矿型结构,而且Ce掺杂催化剂的大部分Ce离子可以进入到LaMnO_(3)结构中.在催化剂适量掺杂Ce后,H_(2)消耗总面积增大、还原峰的峰值温度降低,表明掺杂Ce改善了催化剂的还原特性;同时NO吸附和脱附面积增大,表明Ce掺杂改变了催化剂的NO_(x)吸附-脱附性能. 展开更多
关键词 La_(1-x)Ce_(x)MnO_(3)-Ba/Al_(2)O_(3)催化剂 H_(2)选择性催化还原NO NH_(3)产物选择性 NO转化率 晶相结构 还原特性 NO_(x)吸附-脱附
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One-step synthesis of Pt@ZIF-8 catalyst for the selective hydrogenation of 1,4-butynediol to 1,4-butenediol 被引量:16
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作者 Chuang Li Mingming Zhang +3 位作者 Xin Di Dongdong Yin Wenzhen Li Changhai Liang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1555-1561,共7页
A catalyst consisting of platinum nanoparticles on a ZIF-8 support(Pt@ZIF-8) was synthesized in a straightforward one-step procedure,by adding a nanostructured platinum sol during the formation of ZIF-8 at room temp... A catalyst consisting of platinum nanoparticles on a ZIF-8 support(Pt@ZIF-8) was synthesized in a straightforward one-step procedure,by adding a nanostructured platinum sol during the formation of ZIF-8 at room temperature.Pt@ZIF-8 was highly porous and well crystallized.The Pt nanoparticles were well dispersed within the ZIF-8 support.In the hydrogenation of 1,4-butynediol,Pt@ZIF-8 exhibited high activity,excellent selectivity for 1,4-butenediol of greater than 94%,and reusability.The Pt@ZIF-8 catalyst did not require further additives.The favorable catalytic performance was attributed primarily to the modification of the ZIF-8 support by the platinum nanoparticles. 展开更多
关键词 Platinum sol ZIF-8 One-step synthesis 1 4-Butynediol selective hydrogenation
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Selective brain hypothermia-induced neuroprotection against focal cerebral ischemia/reperfusion injury is associated with Fis1 inhibition 被引量:14
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作者 Ya-Nan Tang Gao-Feng Zhang +6 位作者 Huai-Long Chen Xiao-Peng Sun Wei-Wei Qin Fei Shi Li-Xin Sun Xiao-Na Xu Ming-Shan Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第5期903-911,共9页
Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects... Selective brain hypothermia is considered an effective treatment for neuronal injury after stroke,and avoids the complications of general hypothermia.However,the mechanisms by which selective brain hypothermia affects mitochondrial fission remain unknown.In this study,we investigated the effect of selective brain hypothermia on the expression of fission 1 (Fis1) protein,a key factor in the mitochondrial fission system,during focal cerebral ischemia/reperfusion injury.Sprague-Dawley rats were divided into four groups.In the sham group,the carotid arteries were exposed only.In the other three groups,middle cerebral artery occlusion was performed using the intraluminal filament technique.After 2 hours of occlusion,the filament was slowly removed to allow blood reperfusion in the ischemia/reperfusion group.Saline,at 4℃ and 37℃,were perfused through the carotid artery in the hypothermia and normothermia groups,respectively,followed by restoration of blood flow.Neurological function was assessed with the Zea Longa 5-point scoring method.Cerebral infarct volume was assessed by 2,3,5-triphenyltetrazolium chloride staining,and apoptosis was assessed by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling staining.Fis1 and cytosolic cytochrome c levels were assessed by western blot assay.Fis1 mRNA expression was assessed by quantitative reverse transcription-polymerase chain reaction.Mitochondrial ultrastructure was evaluated by transmission electron microscopy.Compared with the sham group,apoptosis,Fis1 protein and mRNA expression and cytosolic cytochrome c levels in the cortical ischemic penumbra and cerebral infarct volume were increased after reperfusion in the other three groups.These changes caused by cerebral ischemia/reperfusion were inhibited in the hypothermia group compared with the normothermia group.These findings show that selective brain hypothermia inhibits Fis1 expression and reduces apoptosis,thereby ameliorating focal cerebral ischemia/reperfusion injury in rats.Experiments were authorized by the Ethics Committee of Qingdao Municipal Hospital of China (approval No.2019008). 展开更多
关键词 apoptosis Fis1 HYPOTHERMIA ISCHEMIA/REPERFUSION injury mitochondria MITOCHONDRIAL fission MITOCHONDRIAL ultrastructure NEUROPROTECTION selective BRAIN HYPOTHERMIA stroke
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Preparation and characterization of Ce_(1-x)Fe_xO_2 complex oxides and its catalytic activity for methane selective oxidation 被引量:7
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作者 李孔斋 王华 +1 位作者 魏永刚 刘明春 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期245-249,共5页
A series of Ce1-xFexO2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) complex oxide catalysts were prepared using the coprecipitation method. The catalysts were characterized by means of XRD and H2-TPR. The reactions between methane ... A series of Ce1-xFexO2 (x=0, 0.2, 0.4, 0.6, 0.8, 1) complex oxide catalysts were prepared using the coprecipitation method. The catalysts were characterized by means of XRD and H2-TPR. The reactions between methane and lattice oxygen from the complex oxides were investigated. The characteristic results revealed that the combination of Ce and Fe oxide in the catalysts could lower the temperature necessary to reduce the cerium oxide. The catalytic activity for selective CH4 oxidation was strongly influenced by dropped Fe species. Adding the appropriate amount of Fe2O3 to CeO2 could promote the action between CH4 and CeO2. Dispersed Fe2O3 first returned to the original state and would then virtually form the Fe species on the catalyst, which could be considered as the active site for selective CH4 oxidation. The appearance of carbon formation was significant and the oxidation of carbon appeared to be the rate-determining step; the amounts of surface reducible oxygen species in CeO2 were also relevant to the activity. Among all the catalysts, Ce0.6Fe0.402 exhibited the best activity, which converted 94.52% of CH4 at 900 ℃. 展开更多
关键词 Ce1-xFexO2 complex oxides H2-TPR lattice oxygen methane selective oxidation rare earths
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Marker-assisted selection to pyramid Fusarium head blight resistance loci Fhb1 and Fhb2 in the high-quality soft wheat cultivar Yangmai 15
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作者 HU Wen-jing FU Lu-ping +3 位作者 GAO De-rong LI Dong-sheng LIAO Sen LU Cheng-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第2期360-370,共11页
Fusarium head blight(FHB)is one of the most detrimental wheat diseases which greatly decreases the yield and grain quality,especially in the middle and lower reaches of the Yangtze River of China.Fhb1 and Fhb2 are two... Fusarium head blight(FHB)is one of the most detrimental wheat diseases which greatly decreases the yield and grain quality,especially in the middle and lower reaches of the Yangtze River of China.Fhb1 and Fhb2 are two major resistance loci against Fusarium graminearum.Yangmai 15(YM15)is one of the most popular varieties in the middle and lower reaches of the Yangtze River,and it has good weak gluten characters but poor resistance to FHB.Here we used Fhb1 and Fhb2 to improve the FHB resistance of YM15 by a molecular marker-assisted selection(MAS)backcrossing strategy.The selection of agronomic traits was performed for each generation.We successfully selected seven introgressed lines which carry homozygous Fhb1 and Fhb2 with significantly higher FHB resistance than the recurrent parent YM15.Three of the introgressed lines had agronomic and quality characters that were similar to YM15.This study demonstrates that the pyramiding of Fhb1 and Fhb2 could significantly improve the FHB resistance in wheat using the MAS approach. 展开更多
关键词 Fusarium head blight marker-assisted selection Fhb1 Fhb2 resistance breeding WHEAT
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Selective laser melted near-beta titanium alloy Ti-5Al-5Mo-5V-1Cr-1Fe:Microstructure and mechanical properties 被引量:5
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作者 HUANG Hua-long LI Dan +4 位作者 CHEN Chao LI Rui-di ZHANG Xiao-yong LIU Shi-chao ZHOU Ke-chao 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第6期1601-1614,共14页
In this work,a near-beta Ti-5Al-5Mo-5V-1Cr-1Fe titanium alloy was fabricated by selective laser melting(SLM),and the microstructure evolution together with the mechanical properties was studied.The as-fabricated alloy... In this work,a near-beta Ti-5Al-5Mo-5V-1Cr-1Fe titanium alloy was fabricated by selective laser melting(SLM),and the microstructure evolution together with the mechanical properties was studied.The as-fabricated alloy showed columnarβgrains spreading over multiple layers and paralleling to the building direction.The distinct microstructure of as-fabricated alloy was composed of near-β(more than 98.1%)with a submicron cellular structure.Different SLM processing parameters such as hatch spacing could affect the microstructure of as-fabricated alloy,which could thus further significantly affect the mechanical properties of as-fabricated alloy.In addition,the as-fabricated alloy with the distinct microstructure exhibits yield strength of 818 MPa combined with elongation of more than 19%,which shows that SLM is a potential technology for manufacturing near-beta titanium components. 展开更多
关键词 selective laser melting Ti-5Al-5Mo-5V-1Cr-1Fe near-βandβ-titanium alloy cellular structure PRECIPITATION
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敲低结肠癌转移相关基因1促进RSL3诱导的结直肠癌细胞铁死亡
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作者 孙硕 黄鑫 +5 位作者 李国东 张春云 卢泽梅 张伟伟 李泽彦 杨清竹 《南方医科大学学报》 CAS CSCD 北大核心 2024年第1期173-178,共6页
目的探讨结肠癌转移相关基因1(MACC1)对RAS选择性致死化合物3(RSL3)诱导的结直肠癌细胞铁死亡的影响及其分子机制。方法体外培养结直肠癌细胞SW620,HCT116,LOVO及RKO细胞,Western blot实验检测细胞中MACC1表达;以SW620细胞为实验材料,MT... 目的探讨结肠癌转移相关基因1(MACC1)对RAS选择性致死化合物3(RSL3)诱导的结直肠癌细胞铁死亡的影响及其分子机制。方法体外培养结直肠癌细胞SW620,HCT116,LOVO及RKO细胞,Western blot实验检测细胞中MACC1表达;以SW620细胞为实验材料,MTT法检测不同浓度(0、2.5、5、10、20、40μmol/L)铁死亡诱导剂RSL3以及不同浓度(0、5、10、20μmol/L)铁死亡抑制剂Fer-1对SW620细胞存活率的影响,分析单独使用10μmol/L RLS3以及10μmol/L RLS3和10μmol/LFer-1联合作用对SW620细胞存活率的影响,并检测干扰MACC1后不同浓度RSL3对SW620细胞存活率的影响;实时定量RT-PCR和Western blot法检测不同浓度RSL3(0、2.5、5、10μmol/L)对MACC1在mRNA和蛋白水平的影响,并检测干扰MACC1后GPX4在mRNA和蛋白水平的表达;流式细胞仪及激光共聚焦实验检测干扰MACC1后,SW620细胞中脂质过氧化Lipid ROS水平的变化。结果4种结直肠癌细胞中SW620细胞MACC1表达量最高;铁死亡诱导剂RSL3抑制SW620细胞的存活率,细胞存活率随RSL3浓度升高而降低,呈剂量依赖性;不同浓度的铁死亡抑制剂Fer-1对SW620细胞的存活率没有影响;与对照Ctrl组细胞存活率相比,单独使用RSL3细胞存活率降低了50%(P<0.01),而联合使用RSL3与Fer-1处理SW620细胞,细胞的存活率得到恢复(P>0.05);不同浓度的RSL3作用于SW620细胞后,细胞中MACC1基因在mRNA和蛋白水平被显著抑制(P<0.01),具有一定的药物浓度依赖性。siRNA干扰MACC1基因表达后,增强RSL3对SW620细胞毒作用,并抑制细胞中GPX4的表达(P<0.01),增加细胞中Lipid ROS水平(P<0.05)。结论MACC1通过调控GPX4影响RSL3诱导的结直肠癌细胞铁死亡。 展开更多
关键词 RAS选择性致死化合物3 铁死亡 结肠癌转移相关基因1 谷胱甘肽过氧化物酶4
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Effect of Ammonia on the Performance of Catalysts for Selective Hydrogenation of 1-Methylnaphthalene 被引量:4
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作者 Ge Panzhu Ren Liang +1 位作者 Gao Xiaodong Li Dadong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第4期1-7,共7页
The effect of ammonia on the catalytic performance for 1-methylnaphthalene(1-MN) selective hydrogenation saturation was studied with Co-Mo/γ-Al_2O_3, Ni-W/γ-Al_2O_3, Ni-Mo/γ-Al_2O_3, and Ni-Mo-W/γ-Al_2O_3 catalyst... The effect of ammonia on the catalytic performance for 1-methylnaphthalene(1-MN) selective hydrogenation saturation was studied with Co-Mo/γ-Al_2O_3, Ni-W/γ-Al_2O_3, Ni-Mo/γ-Al_2O_3, and Ni-Mo-W/γ-Al_2O_3 catalysts. The results indicated that Ni-Mo-W/γ-Al_2O_3 catalyst exhibited the best performance for saturation of 1-MN. The introduction of NH3 remarkably inhibited the hydrogenation of 1-MN in the dynamic control area, but it had no effect in the thermodynamic control area. Besides, the mono-aromatics selectivity on the Ni-Mo-W and Ni-Mo catalysts was enhanced. However, it had little effect on the Ni-W and Co-Mo catalysts. 展开更多
关键词 1-methylnaphthalene(1-MN) selectivity hydrogenation catalyst hydrogenation saturation
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TS-1分子筛研究进程及催化应用
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作者 杨帆 王怡明 +2 位作者 朱韩英 蒋旭 史晓波 《工业催化》 CAS 2024年第3期29-34,共6页
TS-1是一类独特的用于液相选择性氧化反应的分子筛催化剂,在高结晶沸石框架中具有四面体配位Ti^(4+)离子。TS-1/H_(2)O_(2)绿色反应体系已经取得了相当大的突破。TS-1分子筛的催化性能与其拓扑结构、晶体形态、四面体Ti的含量和反应微... TS-1是一类独特的用于液相选择性氧化反应的分子筛催化剂,在高结晶沸石框架中具有四面体配位Ti^(4+)离子。TS-1/H_(2)O_(2)绿色反应体系已经取得了相当大的突破。TS-1分子筛的催化性能与其拓扑结构、晶体形态、四面体Ti的含量和反应微环境有关。当前石油化工和精细化工等行业对大分子氧化催化剂的需求日益增长,开发催化性能显著提高的新型TS-1的研究成为热点。综述TS-1分子筛近年的研究进展及催化应用。 展开更多
关键词 催化剂工程 TS-1分子筛 骨架钛 选择性氧化 反应晶化 化学改性
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Effect of mesopore spatial distribution of HZSM-5 catalyst on zinc state and product distribution in 1-hexene aromatization
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作者 Chenhao Wei Di Gao +3 位作者 Guohao Zhang Liang Zhao Jinsen Gao Chunming Xu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期16-26,共11页
1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and xylene.Besides,the increasing market demand of xylene has put ... 1-hexene aromatization is a promising technology to convert excess olefin in fluid catalytic cracking(FCC)gasoline to high-value benzene(B),toluene(T),and xylene.Besides,the increasing market demand of xylene has put forward higher requirements for new generation of catalyst.For increasing xylene yield in 1-hexene aromatization,the effect of mesopore structure and spatial distribution on product distribution and Zn loading was studied.Catalysts with different mesopore spatial distribution were prepared by post-treatment of parent HZSM-5 zeolite,including NaOH treatment,tetra-propylammonium hydroxide(TPAOH)treatment,and recrystallization.It was found the evenly distributed mesopore mainly prolongs the catalyst lifetime by enhancing diffusion properties but reduces the aromatics selectivity,as a result of damage of micropores close to the catalyst surface.While the selectivity of high-value xylene can be highly promoted when the mesopore is mainly distributed interior the catalyst.Besides,the state of loaded Zn was also affected by mesopores spatial distribution.On the optimized catalyst,the xylene selectivity was enhanced by 12.4%compared with conventional Zn-loaded parent HZSM-5 catalyst at conversion over 99%.It was attributed to the synergy effect of mesopores spatial distribution and optimized acid properties.This work reveals the role of mesopores in different spatial positions of 1-hexene aromatization catalysts in the reaction process and the influence on metal distribution,as well as their synergistic effect two on the improvement of xylene selectivity,which can improve our understanding of catalyst pore structure and be helpful for the rational design of high-efficient catalyst. 展开更多
关键词 1-Hexene aromatization Alkali treatment Xylene selectivity MESOPORES Zinc state
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The wheat sucrose synthase gene TaSus1 is a determinant of grain number per spike
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作者 Liping Shen Lili Zhang +20 位作者 Changbin Yin Xiaowan Xu Yangyang Liu Kuocheng Shen He Wu Zhiwen Sun Ke Wang Zhonghu He Xueyong Zhang Chenyang Hao Jian Hou Aoyue Bi Xuebo Zhao Daxing Xu Botao Ye Xuchang Yu Ziying Wang Danni Liu Yuanfeng Hao Fei Lu Zifeng Guo 《The Crop Journal》 SCIE CSCD 2024年第1期295-300,共6页
Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The e... Some haplotypes of the sucrose synthase gene TaSus1 are associated with thousand-grain weight(TGW)in wheat(Triticum aestivum L.).However,no mutations have been identified within the gene to test this association.The effects of TaSus1 on grain number per spike(GNS)also are largely unknown.Our previous genome-wide association study identified TaSus-A1 as a candidate gene controlling fertile spikelet number per spike(FSN).In the present study,we generated two independent mutants for the three TaSus1 homoeologs by CRISPR/Cas9-mediated genome editing.The triple mutants displayed lower FSN,GNS,grain number per spikelet(GNST),and TGW than wild-type plants.In 306 hexaploid wheat accessions,two single-nucleotide polymorphisms in TaSus-A1 contributed differently to GNS.Introgression of the two alleles into a wheat genetic background confirmed their effects.The alleles differed in geographical distribution among the accessions. 展开更多
关键词 Domestication selection Fertile spikelet number per spike(FSN) Geographical differentiation Grain number per spike(GNS) TaSus1
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MICROVOLTAMMETRIC STUDIES ON VITAMIN B1 ION-SELECTIVE MICROELECTRODE BASED ON A LIQUID/LIQUID INTERFACE
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作者 Bo HUANG Ba Zhang YU +1 位作者 Pei Biao LI San Fang WU(Department of Chemistry,Wuhan University,Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第6期509-512,共4页
A vitamin Bl(VBl)ion-selective microelectrode based on nitrobenzene and 1,2-dichloroethane/water interfaces at the tip of a dual-section micropipette was.ezamined by using eyclie voltammety, asymmetric sweep rate cycl... A vitamin Bl(VBl)ion-selective microelectrode based on nitrobenzene and 1,2-dichloroethane/water interfaces at the tip of a dual-section micropipette was.ezamined by using eyclie voltammety, asymmetric sweep rate cyclie voltammetryand stripping,voltammetry,.Trace VB1 could be determined down to 4.6×10-6.mol/Lin aqueous saple solution, and some transfer data of VB1 were obtained. 展开更多
关键词 ION selective VITAMIN B1 BASED
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Development and structure-activity relationships of tanshinones as selective 11β-hydroxysteroid dehydrogenase 1 inhibitors
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作者 Xu Deng Su-Ling Huang +6 位作者 Jian Ren Zheng-Hong Pan Yu Shen Hao-Feng Zhou Zhi-Li Zuo Ying Leng Qin-Shi Zhao 《Natural Products and Bioprospecting》 2022年第1期573-585,共13页
11β-Hydroxysteroid dehydrogenase 1(11β-HSD1)represents a promising drug target for metabolic syndrome,includ-ing obesity and type 2 diabetes.Our initial screen of a collection of natural products from Danshen led to... 11β-Hydroxysteroid dehydrogenase 1(11β-HSD1)represents a promising drug target for metabolic syndrome,includ-ing obesity and type 2 diabetes.Our initial screen of a collection of natural products from Danshen led to the identi-fication of tanshinones as the potent and selective 11β-HSD1 inhibitors.To improve the druggability and explore the structure-activity relationships(SARs),more than 40 derivatives have been designed and synthesized using tanshinone IIA and cryptotanshinone as the starting materials.More than 10 derivatives exhibited potent in vitro 11β-HSD1 inhibitory activity and good selectivity over 11β-HSD2 across human and mouse species.Based on the biological results,SARs were further discussed,which was also partially rationalized by a molecular docking model of 1 bound to the 11β-HSD1.Remarkably,compounds 1,17 and 30 significantly inhibited 11β-HSD1 in 3T3-L1 adipocyte and in livers of ob/ob mice,which merits further investigations as anti-diabetic agents.This study not only provides a series of novel selective 11β-HSD1 inhibitors with promising therapeutic potentials in metabolic syndromes,but also expands the boundaries of the chemical and biological spaces of tanshinones. 展开更多
关键词 Metabolic syndrome TANSHINONES selective 11β-HSD1 inhibitors Structure-activity relationships
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叶用芥菜新品种“南冬1号”的选育
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作者 张玉 何自涵 +3 位作者 蒲全明 雍磊 邓慧君 谭明明 《北方园艺》 CAS 北大核心 2024年第16期156-160,F0002,共6页
“南冬1号”是以四川省南充市地方叶用芥菜品种“南充冬菜”为基础种质材料,经多代系统选育而成的芥菜新品种。该品种在四川地区秋季露地种植播收期约120 d,株型半直立,平均株高48 cm,株幅73 cm;板叶,叶色浓绿,叶面微皱,叶片倒卵圆形,... “南冬1号”是以四川省南充市地方叶用芥菜品种“南充冬菜”为基础种质材料,经多代系统选育而成的芥菜新品种。该品种在四川地区秋季露地种植播收期约120 d,株型半直立,平均株高48 cm,株幅73 cm;板叶,叶色浓绿,叶面微皱,叶片倒卵圆形,无刺毛,先端钝圆,叶片边缘呈波状,有效商品叶片数18片左右;平均单株质量1152 g,667 m^(2)平均产量3650 kg;抗霜霉病,抗病毒病。适宜在四川省成都市、南充市、广安市等地的平坝浅丘地区或类似生态区秋季露地种植。2023年通过四川省非主要农作物品种认定委员会认定。 展开更多
关键词 叶用芥菜 新品种 “南冬1号” 系统选育
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山丹丹新品种‘延丹1号’的选育
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作者 毛超 赵鹏飞 齐向英 《延安大学学报(自然科学版)》 2024年第2期30-36,共7页
以山丹丹和兰州百合为亲本,培育山丹丹新品种。通过建立山丹丹和兰州百合无性系,诱导愈伤组织。经过原生质体电融合,细胞培养再分化获得的变异植株。通过籽球培养,室内春化、室外栽培等确定变异植株性状。变异植株为无性繁殖,植株长势强... 以山丹丹和兰州百合为亲本,培育山丹丹新品种。通过建立山丹丹和兰州百合无性系,诱导愈伤组织。经过原生质体电融合,细胞培养再分化获得的变异植株。通过籽球培养,室内春化、室外栽培等确定变异植株性状。变异植株为无性繁殖,植株长势强壮;花色为橘红色,鳞片环抱紧密,抗旱、抗寒性强,耐贫瘠,无明显病虫害。通过在延安市宝塔区、子长市高柏山、宜川县集义镇连续3年以上测试,发现品种稳定性好、异株率低、复花能力强。经过简化基因组分析‘延丹1号’含有山丹丹和兰州百合的基因,确定通过细胞融合培育获得了山丹丹新品种。 展开更多
关键词 山丹丹 延丹1 兰州百合 细胞融合 新品种 无性系选育
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Selective deletion of the soluble Colony-Stimulating Factor 1 isoform in vivo prevents estrogen-deficiency bone loss in mice
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作者 Gang-Qing Yao Nancy Troiano +1 位作者 Christine A Simpson Karl L Insogna 《Bone Research》 SCIE CAS CSCD 2017年第4期367-374,共8页
Neutralizing CSF1 in vivo completely prevents ovariectomy (OVX)-induced bone loss in mice. There are two isoforms of CSF1, soluble (sCSF1), and membrane-bound (mCSF1), but their individual biological functions a... Neutralizing CSF1 in vivo completely prevents ovariectomy (OVX)-induced bone loss in mice. There are two isoforms of CSF1, soluble (sCSF1), and membrane-bound (mCSF1), but their individual biological functions are unclear. It had been previously reported that mCSF1 knockout (K/O) and wild type (Wt) female mice experience the same degree of bone loss following OVX. In Wt mice the expression of sCSF1 was elevated fourfold in skeletal tissue following OVX while expression of mCSF1 was unchanged. To examine the role of sCSF1 in OVX-induced bone loss, mice were engineered in which sCSF1 was not expressed but expression of mCSF1 was unaffected (sCSF1 K/O). Isoform-specific reverse transcription PCR confirmed the absence of transcripts for sCSF1 in bone tissue isolated from these animals and no circulating CSF1 was detected by ELISA. Surprisingly, there were no significant differences in bone mineral density (BMD) between sCSF1 K/O mice and Wt controls as assessed by dual-energy X-ray absorptiometry and micro-CT. However, one month after OVX, femoral, spinal and total BMD had declined by 11.2%, 8.9%, and 8.7% respectively in OVX-Wt animals as compared to Sham-OVX. In contrast OVX sCSF1 K/O mice showed changes of +0.1%, - 2.4%, and +2.3% at the same 3 sites compared to Sham-OVX sCSF1 K/O mice. These data indicate important non-redundant functions for the two isoforms of CSF1 and suggest that sCSF1, but not mCSF1, plays a key role in estrogen-deficiency bone loss. 展开更多
关键词 CSF selective deletion of the soluble Colony-Stimulating Factor 1 isoform in vivo prevents estrogen-deficiency bone loss in mice
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