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Revealing the roles of components in glucose selective hydrogenation into 1,2-propanediol and ethylene glycol over Ni-MnO_x-ZnO catalysts 被引量:2
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作者 Yifan Zan Gai Miao +3 位作者 Hao Wang Lingzhao Kong Yaping Ding Yuhan Sun 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第11期15-19,共5页
MnOx-promoted Ni-based catalyst supported by ZnO was developed to selectively hydrogenate glucose into polyols in water at 523 K with a yield of 64.9%. Using glucose, sorbitol, glycerol and LA as the rawmaterials, the... MnOx-promoted Ni-based catalyst supported by ZnO was developed to selectively hydrogenate glucose into polyols in water at 523 K with a yield of 64.9%. Using glucose, sorbitol, glycerol and LA as the rawmaterials, the roles of nickel, ZnO and MnOx were investigated. The results show that nickel provided a new pathway of glucose to sorbitol and played an important role in the hydrogenation of C3 intermediates to 1,2-propanediol(1,2-PDO). The high yield of 1, 2-PDO was attributed to effective C–C bond cleavage performance of ZnO support promoted by MnOx. ZnO and MnOx contribute to the conversion of glycerol to lactic acid(LA) and LA to 1, 2-PDO, respectively. A concise pathway for hydrogenation of glucose over Ni-based catalyst was proposed. 展开更多
关键词 GLUCOSE Hydrogenation 1 2-propanediol Ethylene GLYCOL NI-BASED catalyst
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Catalytic conversion of ethyl lactate to 1,2-propanediol over CuO 被引量:2
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作者 Song Zhang Zhibao Huo +4 位作者 Dezhang Ren Jiang Luo Jun Fu Lu Li Fangming Jin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第1期126-131,共6页
An efficient conversion of biomass-derived ethyl lactate to 1,2-propanediol(1,2-PDO) over CuO was investigated.Among the catalysts we tested, CuO, Cu2 O and Co showed excellent catalytic activity for the conversion of... An efficient conversion of biomass-derived ethyl lactate to 1,2-propanediol(1,2-PDO) over CuO was investigated.Among the catalysts we tested, CuO, Cu2 O and Co showed excellent catalytic activity for the conversion of ethyl lactate to 1,2-PDO in water, and CuO was more active and gave the best result. The 1,2-PDO yield of 93.6% was achieved when Zn acted as a reductant. The results indicated that in situ formed hydrogen by the oxidation of Zn in water is more effective than gaseous hydrogen, which failed to produce the 1,2-PDO from ethyl lactate.From a practical point of view, the present method may provide a useful route for the production of 1,2-PDO from ethyl lactate. 展开更多
关键词 Biomass 1 2-propanediol Ethyl lactate CuO Hydrothermal reactions
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Catalytic synthesis of cyclohexanone 1,2-propanediol ketal with H_(4)SiW_(12)O_(40)/PAn 被引量:13
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作者 YANG Shuijin YU Xieqing SUN Jutang 《Rare Metals》 SCIE EI CAS CSCD 2004年第4期300-305,共6页
A new environmental friendly catalyst,H_(4)SiW_(12)O_(40)/PAn was prepared andidentified by means of FT-IR,XRD and TG/DTA.Cyclohexanone 1,2-propanediol ketal was synthesizedfrom cyclohexanone and 1,2-propanediol in th... A new environmental friendly catalyst,H_(4)SiW_(12)O_(40)/PAn was prepared andidentified by means of FT-IR,XRD and TG/DTA.Cyclohexanone 1,2-propanediol ketal was synthesizedfrom cyclohexanone and 1,2-propanediol in the presence of H_(4)SiW_(12)O_(40)/PAn The factorsinfluencing tlie synthesis were discussed and the best conditions were found out.The optimumconditions are:molar ratio of cyclohexanone to 1,2-propanediol is 1:1.4,the quantity of catalystis equal to 1.0 percent of feed stocks,and the reaction time is 40 min.H_(4)SiW_(12)O_(40)/PAn is anexcellent catalyst for synthesizing cyclohexanone 1,2-propanediol ketal and its yield can reachover 96.5 percent. 展开更多
关键词 cyclohexanone 1 2-propanediol ketal 12-Tungstosilicic acid POLYANILINE CATALYST KETALATION
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Synthesis of propylene carbonate from urea and 1,2-propanediol 被引量:10
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作者 Zhi Wen Gao Shou Feng Wang Chun Gu Xia 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第2期131-135,共5页
The production of propylene carbonate (PC) from urea and 1,2-propanediol (PG) was investigated in a batch process. The catalytic performances of zinc chloride and magnesium chloride were investigated for this reac... The production of propylene carbonate (PC) from urea and 1,2-propanediol (PG) was investigated in a batch process. The catalytic performances of zinc chloride and magnesium chloride were investigated for this reaction system. The influences of various operation conditions on the PC yield were explored. In this work, MgCl2 and ZnCl2 showed the excellent catalytic activity toward PC synthesis, and the yields of propylene carbonate reached 96.5% and 92.4%, respectively. The optimum reaction conditions were as follows: ethanol/urea molar ratio of 4, catalyst concentration of 1.5%, reaction temperature of 160 ℃, reaction time of 3 h, respectively. The route from urea and 1,2-propanediol shows advantages, such as mild reaction condition and safe operation. The catalytic system is environmentally benign. 展开更多
关键词 UREA 1 2-propanediol Propylene carbonate
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Detection and Analysis of 1,2-propanediol Content in Whole-crop Silage Corn 被引量:1
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作者 Li Yanbing Li Jingchun Shan Anshan 《Animal Husbandry and Feed Science》 CAS 2017年第4期239-242,共4页
[ Objective ] The paper was to investigate the content of 1,2-propanediol in silage feed. [ Method ] Whole-crop corn was stored in laboratory bag silos and outdoor bunker silos. Bag silos were stored for 3, 7, 14, 28,... [ Objective ] The paper was to investigate the content of 1,2-propanediol in silage feed. [ Method ] Whole-crop corn was stored in laboratory bag silos and outdoor bunker silos. Bag silos were stored for 3, 7, 14, 28, 56 and 120 d, respectively, and fermentation products were analyzed after opening; the fermentation products, which were from three 500 t above-ground outdoor bunker silos stored for 120 d, were detected. Eight sampling points were selected for each bunker silo. [ Result] No 1,2-propanediol was detected out in laboratory bag silos, and lactic acid was dominant in fermentation products. The acetic acid content significantly increased ( P 〈 0.05 ) with the extension of storage time, whereas the acetic acid content was kept below one-third of the lactic acid content ; 1,2-propanediol and a small amount of 1-propanol were detected out in three bunker silos, and lactic acid was dominant in fermentation products, whereas the content of acetic acid was slightly lower than that of lactic acid. The differences in fermentation products from different silos and different sites in silos presented heterogeneity; except to propanediol, lactic acid bacteria and yeast, there was no significant difference in fermentation products at the top and bottom layers of silos ( P 〉0.05 ) ; there were significant differences in contents of lactic acid, acetic acid, 1,2-propanediol, and yeast between the outer and inner parts of silos (P 〈 0.05 ) ; except to pH values and acetic acid, there were significant differences in fermentation products between hunker silos (P 〈0. 05). [ Conclusion] No 1,2-propanediol is detected out in laboratory bag silos due to relatively simple fermentation products. However, 1,2-propanediol can be detected in the bunker silos due to complex outdoor environment for silage, and the microorganisms producing 1,2-propanediol exist in silos. 展开更多
关键词 SILAGE 1 2-propanediol Whole-crop corn Fermentation product SILO
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Efficient hydrogenolysis of fructose to 1,2-propanediol over bifunctional Ru-WO_(x)-MgO_(y) catalysts under mild reaction conditions via enhancing the chemoselective cleavage of C-C bonds
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作者 Shuang Luo Tie Shu +6 位作者 Min Mao Haijie Yu Yuxin Zheng Daqian Ding Lingmei Liu Kexin Yao Jianjian Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期311-321,共11页
Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low e... Selective conversion of fructose to 1,2-propanediol(1,2-PDO)is considered as a sustainable and cost-effective alternative to petroleum-based processes,however,this approach still faces challenges associated with low efficiency and harsh reaction conditions.Here,we have successfully synthesized a novel bifunctional Ru-WO_(x)-MgO_(y) catalyst through a facile'one-pot'solvothermal method.Remarkably,this catalyst exhibits exceptional catalytic performances in the conversion of fructose to 1,2-PDO under mild reaction conditions.The yield of 1,2-PDO is up to 56.2%at 140°C for 4 h under an ultra-low hydrogen pressure of only 0.2 MPa,surpassing the reported results in recent literature(below 51%).Comprehensive characterizations and density functional theory(DFT)calculations reveal that the presence of oxygen vacancies in the Ru-WO_(x)-MgO_(y) catalyst,serving as active acidic sites,facilitates the chemoselective cleavage of C-C bonds in fructose,which leads to the generation of active intermediates and ultimately resulted in the high yield of 1,2-PDO. 展开更多
关键词 Biomass FRUCTOSE 1 2-propanediol Retroaldol condensation Heterogenous catalysis
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Interaction between Pd and Cu nanoparticles in bimetallic CuPdx nanoparticles and its impact on oxidation of 1,2-propanediol to aliphatic acids
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作者 Wei Tao Aili Wang Hengbo Yin 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第4期1085-1094,共10页
Bimetallic CuPdx nanoparticles synthesized by the wet chemical reduction method were used as the catalysts in the catalytic oxidation of 1,2-propanediol with gaseous oxygen to aliphatic acids.The palladium and copper ... Bimetallic CuPdx nanoparticles synthesized by the wet chemical reduction method were used as the catalysts in the catalytic oxidation of 1,2-propanediol with gaseous oxygen to aliphatic acids.The palladium and copper nanoparticles in the bimetallic CuP dxnanoparticles had an alloying trend.The catalytic activity of the palladium nanoparticles in the bimetallic CuP dxnanoparticles was enhanced by the interaction between the palladium and copper nanoparticles.When the bimetallic CuPd7 nanoparticles catalyzed the oxidation of 1,2-propanediol in an alkaline aqueous solution at 100℃for 3h,lactic,formic,and acetic acids were dominantly produced with the total selectivity of above 99%at the 1,2-propanediol conversion of 85.9%.The simulation of the reaction kinetic equation on the CuPd7 catalyst showed that the reaction activation energy was 29.4kJ·mol^-1,indicating that the bimetallic CuPd7 nanoparticles had a high catalytic activity in the oxidation reaction between 1,2-propanediol and gaseous oxygen. 展开更多
关键词 Bimetallic CuPdx nanoparticles 1 2-propanediol Aliphatic acids
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Cu,N codoped carbon nanosheets encapsulating ultrasmall Cu nanoparticles for enhancing selective 1,2-propanediol oxidation
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作者 Yonghai Feng Min Yu +2 位作者 Minjia Meng Lei Liu Dewei Rao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第4期27-35,共9页
In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited... In the selective oxidation of biomass-based 1,2-propanediol(PDO)with oxygen as the terminal oxidant,it is challenging to improve the lactic acid(LA)selectivity for nonnoble metal nanoparticles(NPs)due to their limited oxygen reduction rate and easy C-C cleavage.Given the high economic feasibility of nonnoble metals,i.e.,Cu,in this work,copper and nitrogen codoped porous carbon nanosheets encapsulating ultrafine Cu nanoparticles(Cu@Cu-N-C)were developed to realize highly selective of PDO oxidation to LA.The carbon-encapsulated ultrasmall Cu^(0)NPs in Cu@Cu-N-C have high PDO dehydrogenation activity while N-coordinated Cu(Cu-N)sites are responsible for the high oxygen reduction efficacy.Therefore,the performance of catalytic PDO conversion to LA is optimized by a proposed pathway of PDO→hydroxylacetone→lactaldehyde→LA.Specifically,the enhanced LA selectivity is 88.5%,and the PDO conversion is up to 75.1%in an O_(2)-pressurized reaction system(1.0 MPa O_(2)),superior to other Cu-based catalysts,while in a milder nonpressurized system(O_(2)flow rate of 100 mL min-1),a remarkable LA selectivity(94.2%)is obtained with 39.8%PDO conversion,2.2 times higher than that of supported Au nanoparticles(1%Au/C).Moreover,carbon encapsulation offers Cu@Cu-N-C with strong leaching resistance for better recycling. 展开更多
关键词 Selective oxidation Copper and nitrogen doped carbon 1 2-propanediol Ultrasmall Cu nanoparticles Lactic acid
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Asymmetric synthesis of L-carnitine from (R)-3-chloro-1,2-propanediol
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作者 Xu Qin Li Yun Xu Yang Wei Li Wang Bin Hu Hui Min Xue Tian Yi Zhang Xue Tao Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第7期765-767,共3页
A practical chemical synthesis of L-camitine (1) has been accomplished from (R)-3-chloro-1,2-propanediol ((R)-4), which is a main by-product originated from (R,R)-Salen Co(III) catalyzed hydrolytic kinetic... A practical chemical synthesis of L-camitine (1) has been accomplished from (R)-3-chloro-1,2-propanediol ((R)-4), which is a main by-product originated from (R,R)-Salen Co(III) catalyzed hydrolytic kinetic resolution (HKR) of (±)-epichlorohydrin. (R)-4 was utilized as a chiral starting material to prepare the key intermediate cyclic sulfite ((R)-S). The new synthetic approach demonstrated an efficient utilization of organic by-product for the asymmetric synthesis of bioactive compounds. 展开更多
关键词 L-Camitine Cyclic sulfite (R)-3-Chloro-1 2-propanediol
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Synthesis of benzaldehyde 1,2-propanediol acetal catalyzed by SO_4^(2-)/TiO_2-MoO_3-La_2O_3 solid superacid
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作者 YANG Shui-jin XIA Jia GAO Fei 《商丘师范学院学报》 CAS 2007年第12期81-83,共3页
Benzaldehyde 1,2-propanediol acetal was synthesized from benzaldehyde and 1,2-propanediol in the presence of SO42-/TiO2-MoO3-La2O3.The factors influencing the synthesis were discussed and the best conditions were foun... Benzaldehyde 1,2-propanediol acetal was synthesized from benzaldehyde and 1,2-propanediol in the presence of SO42-/TiO2-MoO3-La2O3.The factors influencing the synthesis were discussed and the best conditions were found out.The optimum conditions are:molar ratio of benzaldehyde to 1,2-propanediol is 1:1.8,the quantity of catalyst is equal to 1.0% feed stock,and the reaction time is 1.0 h.SO42-/TiO2-MoO3-La2O3 is an excellent catalyst for synthesizing benzaldehyde 1,2-propanediol acetal and its yield can reach over 77.2%. 展开更多
关键词 苯甲醛-1 2-丙二醇乙缩醛 催化 合成 载体
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Excess Molar Volume, Viscosity and Heat Capacity for the Mixture of 1,2-Propanediol-Water at Different Temperatures 被引量:5
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作者 杨长生 马沛生 +1 位作者 唐多强 靳凤民 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2003年第2期175-180,共6页
Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the... Experimental densities, viscosities and heat capacities at different temperatures were presented over the entire mole fraction range for the binary mixture of 1,2-propanediol and water. Density values were used in the determination of excess molar volumes, VE. At the same time, the excess viscosity was investigated. The values of VE and E were fitted to the Redlich-Kister equation. Good agreement was observed. The excess volumes are negative over the entire range of composition. They show an U-shaped-concentration dependence and decrease in absolute values with increase of temperature. Values of E are negative over the entire range of the composition, and has a trend very similar to that of VE . The analysis shows that at any temperature the specific heat of mixture is a linear function of the composition as x1 > 20%. All the extended lines intersect at one point. An empirical equation is obtained to calculate the specific heat to mixture at any composition and temperature in the experimental range. 展开更多
关键词 VISCOSITY heat capacity DENSITY excess molar volume molecular interaction
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低O_(2)高CO_(2)贮藏环境延缓马铃薯块茎衰老的作用机制
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作者 田甲春 葛霞 +5 位作者 李守强 李梅 田世龙 张亚倩 程建新 李玉梅 《作物学报》 北大核心 2026年第1期262-278,共17页
为探讨低O_(2)高CO_(2)贮藏环境延缓马铃薯块茎的衰老机制,本研究以马铃薯陇薯17号为研究对象,通过测定营养品质、外观指标及生理指标,并结合贮藏中期(60 d)和末期(150 d)的转录组学分析,从表型水平和转录水平研究了马铃薯对低O_(2)高CO... 为探讨低O_(2)高CO_(2)贮藏环境延缓马铃薯块茎的衰老机制,本研究以马铃薯陇薯17号为研究对象,通过测定营养品质、外观指标及生理指标,并结合贮藏中期(60 d)和末期(150 d)的转录组学分析,从表型水平和转录水平研究了马铃薯对低O_(2)高CO_(2)贮藏环境的响应,揭示了马铃薯贮藏的分子调控机制。低O_(2)高CO_(2)贮藏环境延缓了马铃薯在低温贮藏期间淀粉含量的下降及还原糖含量的上升,抑制了薯块发芽和失水,保持了良好的薯皮色泽,抑制了PAL活性、POD活性的上升,并且对3种内源激素有积极的调控作用。与对照相比,贮藏中期共发现741个差异基因,其中上调基因378个,下调基因363个。贮藏至末期时,差异基因总数上升为1658个,其中上调基因为1211个,下调基因为447个。通过生物信息学分析发现,低O_(2)高CO_(2)贮藏环境显著调控与苯丙烷生物合成代谢、淀粉和蔗糖代谢、植物激素信号转导及MPAK信号转导相关的代谢途径。综上所述,本研究为马铃薯的气调贮藏提供了理论基础,为进一步研究分子机制提供了理论依据。 展开更多
关键词 马铃薯 低O_(2)高CO_(2) 延缓衰老 转录组学 代谢途径
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橙黄瓤西瓜新品种“炫美2号”的选育
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作者 穆生奇 张莹 +3 位作者 胡潇怡 曾剑波 马超 石颜通 《北方园艺》 北大核心 2026年第5期157-160,F0002,共5页
“炫美2号”是以‘M114’为母本,以‘N213’为父本选育出的小果型西瓜新品种。早熟,果实发育期28~30 d,全生育期88~90 d。植株生长势中等,低温下易坐果。果实椭圆形,有果皮蜡粉,平均单果质量2.09 kg,果皮厚度0.5 cm。果皮绿,上覆墨绿色... “炫美2号”是以‘M114’为母本,以‘N213’为父本选育出的小果型西瓜新品种。早熟,果实发育期28~30 d,全生育期88~90 d。植株生长势中等,低温下易坐果。果实椭圆形,有果皮蜡粉,平均单果质量2.09 kg,果皮厚度0.5 cm。果皮绿,上覆墨绿色条纹,果肉橙黄色,中心可溶性固形物含量13.0%,边缘可溶性固形物含量10.6%。果皮韧,肉质脆,667 m^(2)产量3200 kg以上,2023年9月通过农业农村部非主要农作物品种登记。 展开更多
关键词 小型西瓜 新品种 “炫美2号”
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VUV/Fe^(2+)/Ox类芬顿体系对偶氮染料酸性红G的降解机理研究
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作者 王坤 陈伟 +5 位作者 唐玉朝 崔康平 伍昌年 朱先胜 孙海翔 黄显怀 《中国环境科学》 北大核心 2026年第2期785-796,共12页
构建了一种基于真空紫外(VUV)/Fe^(2+)/草酸(Ox)的新型无外源氧化剂类芬顿反应体系,并将其应用于偶氮染料酸性红G(ARG)的降解研究.结果表明,该体系可实现H_(2)O_(2)的动态释放,进而与Fe^(2+)形成类芬顿反应,且在较宽pH值范围内均能保持... 构建了一种基于真空紫外(VUV)/Fe^(2+)/草酸(Ox)的新型无外源氧化剂类芬顿反应体系,并将其应用于偶氮染料酸性红G(ARG)的降解研究.结果表明,该体系可实现H_(2)O_(2)的动态释放,进而与Fe^(2+)形成类芬顿反应,且在较宽pH值范围内均能保持高反应活性.结果表明:在ARG初始质量浓度为60mg/L、Fe^(2+)与Ox浓度分别为0.06和0.7mmol/L的条件下,VUV/Fe^(2+)/Ox体系对ARG的去除率在5min内即可达到96.2%,其降解过程符合准一级动力学模型.随着溶液初始pH值的升高,ARG去除率呈下降趋势,在pH=7时,一级速率常数k值仍可达0.454min⁻1,为pH=3时的69.6%,表明该体系在中性条件下仍能维持较高反应活性.反应初始5min内,体系中H_(2)O_(2)浓度逐渐上升至最高62.5µmol/L,随后缓慢下降,至9min时仍保持在51.8µmol/L.自由基捕获实验与EPR检测结果共同证实,羟基自由基(·OH)和超氧自由基(O_(2)^(·-))是该体系中的主要活性氧化物种.此外,水环境中常见的无机阴离子(HCO_(3)^(-)、NO_(3)^(-)、Cl^(-)、SO_(4)^(2-))均会对ARG降解产生不同程度的抑制作用.通过紫外可见吸收光谱及液相色谱-质谱联用(LC-MS)分析可知,降解过程中生成的活性氧(ROS)通过攻击ARG分子中的偶氮键和苯环结构,实现了染料的脱色与去除. 展开更多
关键词 VUV/Fe^(2+)/草酸体系 类芬顿反应 酸性红G 动态H_(2)O_(2)释放
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CO_(2)气氛条件下单基药的能量释放过程及规律研究
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作者 李成龙 丁亚军 肖忠良 《含能材料》 北大核心 2026年第2期122-129,共8页
针对发射药/超临界二氧化碳(SC-CO_(2))在弹射做功方面的应用潜力需求,通过与N_(2)环境对比开展了热分析、静态燃烧与密闭燃烧试验,研究了单基药在CO_(2)的热分解与燃烧特性。结果表明,CO_(2)环境明显抑制单基药热解过程,其活化能最大值... 针对发射药/超临界二氧化碳(SC-CO_(2))在弹射做功方面的应用潜力需求,通过与N_(2)环境对比开展了热分析、静态燃烧与密闭燃烧试验,研究了单基药在CO_(2)的热分解与燃烧特性。结果表明,CO_(2)环境明显抑制单基药热解过程,其活化能最大值较N_(2)环境升高15.53 kJ·mol^(-1);单基药在CO_(2)环境下燃烧时间显著延长,7 MPa时较N_(2)环境增加1729 ms,且SC-CO_(2)中单基药燃烧火焰呈现内白外淡红的特殊形貌;密闭燃烧时,液态CO_(2)相变吸热导致单基药点火延迟达12.20 ms,单基药在SC-CO_(2)环境下作用时间处于10^(-2) s量级。初始压力增加有助于提升单基药在SC-CO_(2)环境下能量释放速率。 展开更多
关键词 单基发射药 CO_(2)相变 能量释放 超临界二氧化碳(SC-CO_(2)) 火焰形貌
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废弃煤矿巷道CO_(2)“封存-利用”技术探索及转化效率研究
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作者 来兴平 雷彤 +3 位作者 张楠 胡添龙 介凯 刘旭超 《西安科技大学学报》 北大核心 2026年第1期15-26,共12页
为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧... 为应对全球二氧化碳减排的需求,探索利用废弃煤矿地下空间实现CO_(2)封存与资源化利用的新路径,以提升其环境与资源效益。提出了包含捕集、封存、转化、分离系统的废弃煤矿巷道CO_(2)“封存-利用”一体化技术,基于几何相似理论与固体氧化物电解池(SOEC)技术构建巷道反应硐室与实验室微型反应腔之间尺度映射关系,形成室内试验-井下应用的参数对应体系;通过开展恒电流共电解试验以及气相色谱对气体成分分析,系统揭示反应温度与CO_(2)/H_(2)O气体比例对CO_(2)转化效率的影响。结果表明:在保持A/V不变的条件下,巷道反应硐室尺寸为2.4 m×6 m×3.6 m,对应有效反应面积为384 m^(2);法拉第效率随着温度的升高呈现出“先下降后升高”的特征,随着CO_(2)/H_(2)O气体比例的增加而降低,CO_(2)转化率随着温度升高而显著提升,随着CO_(2)/H_(2)O气体比例增加而降低,在温度为850℃、气体比例CO_(2)∶H_(2)O=1∶1的共电解条件下,CO_(2)实现最优转化效率,转化率达72.22%,法拉第效率为61.77%。研究为实现废弃煤矿巷道CO_(2)封存与高值化利用提供了理论依据与技术支撑。 展开更多
关键词 废弃煤矿 固体氧化物电解池 CO_(2)/H_(2)O共电解 法拉第效率 CO_(2)转化率 相似理论
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纳米SiO_(2)改性蓖麻油基水性聚氨酯的制备及其性能研究
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作者 刘运学 虎悦 +3 位作者 范兆荣 谷亚新 李香玉 王晓丹 《化工新型材料》 北大核心 2026年第3期124-129,共6页
以蓖麻油(CO)、异佛尔酮二异氰酸酯(IPDI)等为主要原料,制备了蓖麻油基水性聚氨酯(CO-WPU)乳液。使用硅烷偶联剂KH550对纳米SiO_(2)进行表面改性,将改性后的纳米SiO_(2)以不同比例与CO-WPU乳液混合,得到纳米SiO_(2)改性蓖麻油基水性聚... 以蓖麻油(CO)、异佛尔酮二异氰酸酯(IPDI)等为主要原料,制备了蓖麻油基水性聚氨酯(CO-WPU)乳液。使用硅烷偶联剂KH550对纳米SiO_(2)进行表面改性,将改性后的纳米SiO_(2)以不同比例与CO-WPU乳液混合,得到纳米SiO_(2)改性蓖麻油基水性聚氨酯涂膜,研究了改性纳米SiO_(2)含量对CO-WPU乳液性能及涂膜性能的影响。利用傅里叶变换红外光谱仪和扫描电子显微镜对改性纳米SiO_(2)的分子结构和微观形貌进行表征,通过热重分析仪测试了CO-WPU涂膜的耐热性能,采用万能试验机测试了CO-WPU涂膜的力学性能。结果表明:硅烷偶联剂KH550与纳米SiO_(2)表面结合,改性纳米SiO_(2)分散性能良好,无明显团聚现象;当改性纳米SiO_(2)质量分数为2.0%时,制备的乳液外观呈乳白色、泛蓝光,稳定性好,满足至少6个月的储存周期,乳液黏度为173.91mPa·s;制备的涂膜综合性能好,涂膜外观光滑,表干时间为35min,铅笔硬度为4H,吸水率为8.67%,接触角为92.430°,拉伸强度为24.0MPa,断裂伸长率为378%,热稳定性良好。 展开更多
关键词 水性聚氨酯 蓖麻油 纳米SIO 2 吸水率 力学性能
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WO_(3)和TiO_(2)共掺V_(2)O_(5)复合薄膜的制备及其光电特性
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作者 王伟 李毅 +1 位作者 刘红薇 施张庆 《电子元件与材料》 北大核心 2026年第1期9-17,共9页
选用五氧化二钒、三氧化钨、二氧化钛粉末和过氧化氢溶液为原料,采用溶胶-凝胶法和后退火工艺在氟掺杂氧化锡导电玻璃基底上制备了三氧化钨和二氧化钛共掺五氧化二钒复合薄膜。通过场发射扫描电子显微镜、X射线衍射仪和X射线光电子能谱... 选用五氧化二钒、三氧化钨、二氧化钛粉末和过氧化氢溶液为原料,采用溶胶-凝胶法和后退火工艺在氟掺杂氧化锡导电玻璃基底上制备了三氧化钨和二氧化钛共掺五氧化二钒复合薄膜。通过场发射扫描电子显微镜、X射线衍射仪和X射线光电子能谱仪等表征了最佳配比下复合薄膜的表面形貌、结构和化学组成,利用分光光度计等测试手段分析了复合薄膜的光电特性。结果表明,在400~1200 nm波长范围内,复合薄膜在室温下的平均透过率为52.99%。当温度从室温升至400℃时,复合薄膜的电阻和透过率变化幅度分别达到83.7%和16.12%。在0~3.1 V的偏压下,复合薄膜的透过率随电压的增大而升高,在400~1200 nm波长范围内,平均透过率升高约12.21%;当偏压大于3.1 V时,复合薄膜的透过率随电压的增大而降低。经过多次高低温循环测试,该复合薄膜的光电特性具有较好的可逆热致光电性,在新型光电器件和传感器等领域展现出潜在应用前景。 展开更多
关键词 复合薄膜 V_(2)O_(5) TiO_(2) WO_(3) 溶胶-凝胶 光电特性
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2型糖尿病患者血浆外泌体微小RNA筛选及验证的研究
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作者 刘晓田 常高华 +7 位作者 何亚玲 任孝颖 江玉洁 蒋喜丽 侯建 李玉倩 张振中 王重建 《中国糖尿病杂志》 北大核心 2026年第1期2-7,共6页
目的筛选并验证T2DM患者相关血浆外泌体微小RNA(miRNA),评价差异miRNA对T2DM的预测能力。方法选取“河南农村队列”2020年驻马店现场随访的T2DM患者52例及同期非DM者52例,采用三阶段1:1匹配为发现集T2DM(DT2DM,n=5)组、发现集对照(DCon,... 目的筛选并验证T2DM患者相关血浆外泌体微小RNA(miRNA),评价差异miRNA对T2DM的预测能力。方法选取“河南农村队列”2020年驻马店现场随访的T2DM患者52例及同期非DM者52例,采用三阶段1:1匹配为发现集T2DM(DT2DM,n=5)组、发现集对照(DCon,n=5)组、验证集T2DM(VT2DM,n=15)组、验证集对照(VCon,n=15)组、靶向验证集T2DM(TT2DM,n=32)组和靶向验证集对照(TCon,n=32)组。采用外泌体miRNA测序技术对血浆外泌体miRNA进行测序,qRT-PCR检测关键差异miRNA水平,Spearman相关分析miRNA与FPG、FIns的相关性,Logistic回归分析miRNA对T2DM的影响,受试者工作特征(ROC)曲线评价关键miRNA对T2DM的预测价值。结果DT2DM组心率、FPG、外泌体浓度高于DCon组(P<0.05)。VT2DM组TG、FPG、FIns、腹型肥胖比例高于VCon组(P<0.05)。TT2DM组WC、TG、FPG、高血压病比例高于TCon组(P<0.05)。两阶段测序结果显示,DT2DM、VT2DM组外泌体关键miRNA miR-3120-5p表达水平均高于DCon、VCon组。Spearman相关分析显示,校正混杂因素后,miR-3120-5p与FPG呈正相关(r=0.311,P=0.016)。Logistic回归分析显示,校正混杂因素后,外泌体miR-3120-5p表达水平是T2DM的影响因素(OR 1.566,95%CI 1.177~2.057)。ROC曲线分析显示,外泌体miR-3120-5p诊断T2DM的曲线下面积为0.75,敏感度为81%,特异度为66%,截断值为7.28。结论miR-3120-5p在T2DM患者血浆外泌体中高表达,并对其具有良好的预测价值,但需在大样本多中心队列人群中进一步验证。 展开更多
关键词 糖尿病 2 外泌体 微小RNA 血浆 病例对照研究
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等离子喷涂Al_(2)O_(3)-40%TiO_(2)强化聚四氟乙烯不粘涂层的制备及其性能研究
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作者 曹达华 高岩 +4 位作者 雒晓涛 申继豪 程志喜 万鹏 李洪伟 《表面技术》 北大核心 2026年第3期252-261,共10页
目的针对传统不粘涂层耐磨性差、表面磨损后疏水性快速衰减等问题,提出一种离散Al_(2)O_(3)-40%TiO_(2)(AT40)陶瓷凸起结构强化的聚四氟乙烯(PTFE)耐磨不粘涂层结构设计,在摩擦磨损中,通过高硬度的陶瓷凸起对摩擦副的支撑作用,避免PTFE... 目的针对传统不粘涂层耐磨性差、表面磨损后疏水性快速衰减等问题,提出一种离散Al_(2)O_(3)-40%TiO_(2)(AT40)陶瓷凸起结构强化的聚四氟乙烯(PTFE)耐磨不粘涂层结构设计,在摩擦磨损中,通过高硬度的陶瓷凸起对摩擦副的支撑作用,避免PTFE被快速磨除,以提高不粘涂层的耐磨性。方法首先,采用等离子喷涂半熔化粒子沉积具有高表面粗糙度的AT40陶瓷涂层;其次,采用PTFE填充AT40陶瓷涂层表面半熔化粒子凸起间的空隙,获得复合涂层。研究喷涂距离对AT40涂层表面结构的影响,揭示AT40涂层表面粗糙度对复合涂层耐磨性能及持久不粘性能的影响规律。结果当喷涂距离从40mm分别提高到80、120、150mm时,等离子喷涂AT40陶瓷涂层的表面粗糙度先减小后增加,在喷涂距离为40mm时,粗糙度Ra最高,为19.3μm,R_(z)为220.4μm。将该条件下制备的AT40陶瓷涂层表面涂覆PTFE面层后,在摩擦磨损25000周后依然能够保持不粘性能,相较于传统的PTFE不粘涂层提升了约4倍。结论大气等离子喷涂的高粗糙度AT40陶瓷底层与PTFE面层的复合耐磨不粘涂层具有优异的耐磨性能和持久的不粘性能,可大幅提升不粘烹饪器皿的使用寿命。 展开更多
关键词 等离子喷涂 Al_(2)O_(3)-40%TiO_(2)/PTFE复合涂层 表面微凸结构 耐磨性 疏水性
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