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Solid Acid Used as Highly Efficient Catalyst for Esterification of Free Fatty Acids with Alcohols 被引量:6
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作者 Zhang Qiuyun Li Hu +4 位作者 Qin Wenting Liu Xiaofang Zhang Yuping Xue Wei Yang Song 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2013年第1期19-24,共6页
Anovel solid acid catalyst, which was prepared from sodium alginate (SA) and metal chlorides and characterized with XRD and FT-IR spectrometry, was used for the preparation of biodiesel via esterification reaction. Th... Anovel solid acid catalyst, which was prepared from sodium alginate (SA) and metal chlorides and characterized with XRD and FT-IR spectrometry, was used for the preparation of biodiesel via esterification reaction. The study results showed that the aluminum-alginate complex prepared in a cheap and easy way exhibited high catalytic activity, and a 92.6% conversion of methyl oleate was obtained in the presence of 4m% of catalyst dosage upon refluxing for 3h of methanol and acid mixed in a molar ratio of 10:1. It should be noted that the catalyst can be applied to the esterification reaction of fatty acids with various carbon chain length on methanol or different short chain alcohols, indicating that the catalyst is suitable for the preparation of biodiesel from waste oils with a high acid value. 展开更多
关键词 sodium alginate solid acid ESTERIFICATION BIODIESEL
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A Hypothesis Regarding the Origin of Additional Surface Acidity in Solid Complexes with Same Metal Cations
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作者 SHAO Bo TONG Chaoli +5 位作者 WANG Jiaqian HAN Zhongkang ZHANG Yan GE Wenfeng WANG Yong YANG Hangsheng 《材料科学与工程学报》 CAS CSCD 北大核心 2024年第5期718-722,共5页
Based on the criteria for additional surface acidity generation in composite oxides and composite fluorides proposed by Tanabe and Kemnitz et al.A hypothesis for the origin of additional surface acidity in solid compo... Based on the criteria for additional surface acidity generation in composite oxides and composite fluorides proposed by Tanabe and Kemnitz et al.A hypothesis for the origin of additional surface acidity in solid composites with the same metal cations is proposed.The surface acidsites of We analyze three types of solid composite systems,that is,CrF_(3)/Cr_(2)O_(3),MgF_(2)/MgO,and ZnF_(2)/ZnO,is systematically analyzed,which agrees with experimental results.Accordingly,the origin of additional surface acidity in these solid composites is reasonably explained,and the types of acidic sites are also predicted. 展开更多
关键词 Surface acidity solid composite Local charge imbalance
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Catalytic Performance of Aquathermolysis and Viscosity Reduction of Heavy Oil over a WO_(3)/ZrO_(2) Solid Acid
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作者 Ning Haolong Wu Junwen +6 位作者 Shen Zhibing Che Chang Tang Ruiyuan Liang Shengrong Zhang Juntao Jiang Haiyan Yuan Shibao 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期82-92,共11页
Tungstated zirconia(WO_(3)/ZrO_(2))solid acid catalysts with different WO_(3) contents were prepared by a hydrothermal method and then used in the catalytic aquathermolysis of heavy oil from Xinjiang.The WO_(3)/ZrO_(2... Tungstated zirconia(WO_(3)/ZrO_(2))solid acid catalysts with different WO_(3) contents were prepared by a hydrothermal method and then used in the catalytic aquathermolysis of heavy oil from Xinjiang.The WO_(3)/ZrO_(2) solid acid catalyst was characterized by a range of characterization methods,including X-ray diffraction,NH3-temperature programmed desorption,and pyridine infrared spectroscopy.The WO_(3) content of the WO_(3)/ZrO_(2) catalysts had an important impact on the structure and property of the catalysts.When the WO_(3) mass fraction was 20%,it facilitated the formation of tetragonal zirconia,thereby enhancing the creation of robust acidic sites.Acidity is considered to have a strong impact on the catalytic performance of the aquathermolysis of heavy oil.When the catalyst containing 20%WO_(3) was used to catalyze the aquathermolysis of heavy oil under conditions of 14.5 MPa,340℃,and 24 h,the viscosity of heavy oil decreased from 47266 to 5398 mPa·s and the viscosity reduction rate reached 88.6%.The physicochemical properties of heavy oil before and after the aquathermolysis were analyzed using a saturates,aromatics,resins,and asphaltenes analysis,gas chromatography,elemental analysis,densimeter etc.After the aquathermolysis,the saturate and aromatic contents significantly increased from 43.3%to 48.35%and 19.47%to 21.88%,respectively,with large reductions in the content of resin and asphaltene from 28.22%to 25.06%and 5.36%to 2.03%,respectively.The sulfur and nitrogen contents,and the density of the oil were significantly decreased.These factors were likely the main reasons for promoting the viscosity reduction of heavy oil during the aquathermolysis over the WO_(3)/ZrO_(2) solid acid catalysts. 展开更多
关键词 heavy oil AQUATHERMOLYSIS viscosity reduction WO_(3)/ZrO_(2)solid acid catalyst
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Protonated and layered transition metal oxides as solid acids for dehydration of biomass-based fructose into 5-hydroxymethylfurfural
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作者 Jiawei Zhong Yuanyuan Guo Jinzhu Chen 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2017年第1期147-154,共8页
A serial of protonated and layered transition metal oxides, including layered HTaWO6, HNbMoO6 as well as HNbWO6, were synthesized by solid-state reaction and ion-exchange. The layered HTaWO6 has been systematically st... A serial of protonated and layered transition metal oxides, including layered HTaWO6, HNbMoO6 as well as HNbWO6, were synthesized by solid-state reaction and ion-exchange. The layered HTaWO6 has been systematically studied as a solid acid to realize the dehydration of fructose to 5-hydroxymethylfurfural (HMF). The transition metal oxide samples were characterized with ICP-OES, EDS, XRD, XPS, SEM, TGA, FT-IR, N-2 adsorption-desorption and NH3-TPD. The influential factors such as reaction temperature, reaction time, solvent, catalyst amount and substrate concentration were deeply investigated. The optimized fructose conversion rate of 99% with HMF yield of 67% were achieved after 30 min at 140 degrees C in dimethylsulfoxide. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 展开更多
关键词 BIOMASS DEHYDRATION 5-HYDROXYMETHYLFURFURAL Layered transition metal oxide solid acid
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Acetalization of carbonyl compounds with 2,2,4-trimethyl-1,3-pentanedio catalyzed by novel carbon based solid acid catalyst 被引量:3
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作者 Ling Liu Yuechang Zhao Shan Gan Xuezheng Liang Jianguo Yang Mingyuan He 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期149-152,共4页
The synthesis of 2, 4-diisopropyl-5,5-dimethy1- 1.3-dioxane through the acetalization of isobutyraldehyde with 2, 2, 4-trimethy1-1,3-pentanediol (TMPD) catalyzed by the novel carbon based acid was first carried out.... The synthesis of 2, 4-diisopropyl-5,5-dimethy1- 1.3-dioxane through the acetalization of isobutyraldehyde with 2, 2, 4-trimethy1-1,3-pentanediol (TMPD) catalyzed by the novel carbon based acid was first carried out. High conversion (≥98%) and specific selectivity were obtained using the novel carbon based acid, which kept high activity after it was reused 5 times. Moreover. the catalyst could be used to catalyze the acetalization and ketalization of different aldehydes and ketones with superior yield. The yield of several products was over 90%. The novel heterogeneous catalyst has the distinct advantages of high activity, strikingly simple workup procedure, non-pollution, and reusability, which will contribute to the success of the green process greatly. 展开更多
关键词 TMPD ACETALIZATION carbon based solid strong acid isobutylaldehyde
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高温碳酸盐岩储层酸压固态延迟酸在裂缝中作用规律数值模拟
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作者 罗攀登 张士诚 +3 位作者 张雄 牟建业 郑海钱 卢盼盼 《大庆石油地质与开发》 北大核心 2025年第2期79-88,共10页
酸压是低渗透碳酸盐岩储层增产改造的主要方式。在高温碳酸盐岩储层中常规酸作用距离短,常使用自生酸提高酸液作用距离,自生酸中的固态延迟酸在油田使用较广,但考虑温度影响固态延迟酸作用规律的模拟与研究较少。针对该问题,首先建立固... 酸压是低渗透碳酸盐岩储层增产改造的主要方式。在高温碳酸盐岩储层中常规酸作用距离短,常使用自生酸提高酸液作用距离,自生酸中的固态延迟酸在油田使用较广,但考虑温度影响固态延迟酸作用规律的模拟与研究较少。针对该问题,首先建立固态延迟酸生酸模型;其次,通过物质守恒、能量守恒、动量守恒及酸岩反应动力学原理,构建酸压中固态延迟酸作用模型;最后,采用数值求解方法,编制程序进行模拟计算。结果表明:固态延迟酸在无反应条件下生酸浓度可达到纯HCl的11.4%(质量分数),在裂缝中流动、反应条件下,生酸浓度约为纯HCl的6%(质量分数);在近井地带(距井40m)滤失降温作用导致酸蚀缝宽变化明显;中深部裂缝,有无考虑酸岩反应生热使得酸液温度相差最高40℃;相较于交联酸,固态延迟酸具有缓慢释放、增加活酸作用距离的优势;在典型施工条件组合下,预测固态延迟酸作用距离可达140~180m。研究成果可为高温碳酸盐岩储层酸压中固态延迟酸的应用提供了理论依据。 展开更多
关键词 固态延迟酸 生酸规律 裂缝温度场 建模 酸压 活酸作用距离 碳酸盐岩储层
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冶炼铜渣中Fe的常压酸浸溶出规律及动力学分析
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作者 阎崔蓉 张浩 +4 位作者 周新涛 罗中秋 蔡秀楠 高梓猛 时金钰 《华南理工大学学报(自然科学版)》 北大核心 2025年第3期127-138,共12页
冶炼铜渣富含Fe、Si等有价元素,具有优异的二次资源特性,可作为原料构建高附加值硅铁基功能材料。掌握酸浸条件下Si、Fe元素的可控释放规律及矿物相的有效分离机制,是其高值资源化利用的关键。该文采用HSC 6.0模拟硅铁物系在不同pH和电... 冶炼铜渣富含Fe、Si等有价元素,具有优异的二次资源特性,可作为原料构建高附加值硅铁基功能材料。掌握酸浸条件下Si、Fe元素的可控释放规律及矿物相的有效分离机制,是其高值资源化利用的关键。该文采用HSC 6.0模拟硅铁物系在不同pH和电位条件下的优势物种,研究H_(2)SO_(4)酸浸条件下渣中含铁矿物相的溶出条件及Si、Fe元素的可控释放规律,考察了酸浸温度、H_(2)SO_(4)浓度、粒径和搅拌速度等因素对Fe浸出率的影响。结果表明:酸浸温度与H_(2)SO_(4)浓度对Fe浸出率呈正向影响,粒径对Fe浸出率呈负向影响,而搅拌速度的影响甚微;在H_(2)SO_(4)浓度为2.0 mol/L、酸浸温度为90℃、铜渣粒径为(45,88]μm的条件下,酸浸60 min后,铁的浸出率可达95.73%。选择收缩未反应芯模型来描述该酸浸过程,在反应初始阶段,其反应速率主要受化学反应过程的控制,其活化能为40.99 kJ/mol,随后转为内扩散控制,活化能为8.70 kJ/mol。在化学反应控制阶段,计算得到H_(2)SO_(4)浓度和铜渣粒径的影响指数分别为0.558和-0.759,从而确定了H_(2)SO_(4)常压浸取冶炼铜渣的宏观动力学方程。 展开更多
关键词 冶炼铜渣 常压酸浸 Fe酸浸动力学 收缩未反应芯模型 固-液非均相反应
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一种用于固体推进剂样品无机组分含量测定的绿色预处理技术
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作者 程秋霞 薛小慧 +2 位作者 李佳佳 张慧 廉建彪 《爆破器材》 北大核心 2025年第2期51-57,共7页
利用密闭红外加热消解技术与化学法吸收酸烟相结合的绿色预处理方法,对需测定无机组分含量的固体推进剂样品进行了湿法分解预处理,并吸收反应产生的有害酸烟。结果表明:红外加热硝化时,以电炉10%功率预热5 min后,以30%功率加热30 min,再... 利用密闭红外加热消解技术与化学法吸收酸烟相结合的绿色预处理方法,对需测定无机组分含量的固体推进剂样品进行了湿法分解预处理,并吸收反应产生的有害酸烟。结果表明:红外加热硝化时,以电炉10%功率预热5 min后,以30%功率加热30 min,再以70%功率持续加热40 min,测得推进剂中燃烧催化剂的含量符合要求;当以电炉10%功率预热5 min后,以30%功率加热30 min,再以50%功率持续加热60 min,测得推进剂中炭黑的含量符合要求;用质量分数为30%的碱液进行两级吸收,实现了酸烟的零排放。该方法操作简单,准确度和精密度高,可用于固体推进剂无机组分含量测定过程中样品的预处理。 展开更多
关键词 固体推进剂 酸烟 红外加热硝化 绿色预处理
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忻州市不同企业黄酒理化性质的测定分析
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作者 姜宁 周丽娜 《食品安全导刊》 2025年第3期91-94,共4页
代县黄酒是山西省忻州市的特色产品之一,但是多年来受酿酒技术影响,黄酒生产厂家酿造黄酒的水平参差不齐,集中体现在总糖、非糖固形物、氨基酸态氮等各项理化指标。为帮助企业生产出合格且质量稳定的黄酒,从送检忻州市综合检验检测中心... 代县黄酒是山西省忻州市的特色产品之一,但是多年来受酿酒技术影响,黄酒生产厂家酿造黄酒的水平参差不齐,集中体现在总糖、非糖固形物、氨基酸态氮等各项理化指标。为帮助企业生产出合格且质量稳定的黄酒,从送检忻州市综合检验检测中心的样品中筛选9家企业的9个样品(主要是半甜黄酒)进行理化性质检测与分析。结果发现,9家黄酒企业的黄酒总糖含量平均值为73.41 g·L^(-1),非糖固形物含量平均值为16.81 g·L^(-1),总酸含量平均值为6.24 g·L^(-1),氨基酸态氮含量平均值为00.32 g·L^(-1),pH值为3.5~3.9,氧化钙含量均在0.2 g·L^(-1)以下。在9家企业中,以非糖固形物和氨基酸态氮为指标进行判断,发现代号为DXHJ-7的企业生产的黄酒品质较好。但是,代县黄酒的氨基酸态氮含量比绍兴黄酒低,表明忻州市黄酒生产企业的黄酒生产工艺有待进一步优化。 展开更多
关键词 代县黄酒 理化性质 非糖固形物 氨基酸态氮
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顶空箭形固相微萃取-气相色谱-质谱法测定食盐中9种短链脂肪酸
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作者 徐婧婧 吴肖肖 +3 位作者 蒋迪尧 张驰 褚兰玲 纪晗旭 《食品安全质量检测学报》 2025年第7期248-254,共7页
目的建立顶空箭形固相微萃取-气相色谱-质谱法测定食盐中短链脂肪酸的定性和定量分析方法。方法在食盐样品中加入磷酸溶液,基于箭形固相微萃取技术对短链脂肪酸进行萃取富集,探究了萃取头、萃取温度、萃取时间、孵育时间对萃取效果的影... 目的建立顶空箭形固相微萃取-气相色谱-质谱法测定食盐中短链脂肪酸的定性和定量分析方法。方法在食盐样品中加入磷酸溶液,基于箭形固相微萃取技术对短链脂肪酸进行萃取富集,探究了萃取头、萃取温度、萃取时间、孵育时间对萃取效果的影响,目标物用气相色谱-质谱法检测,外标法定量。结果萃取头100μm Polyacrylate对短链脂肪酸有较好的选择性,在萃取温度40℃、时间30 min,解析时间5 min,孵育时间20 min的条件下,9种短链脂肪酸线性关系良好,相关系数大于0.995,检出限为0.25~25.00μg/kg,回收率为92.2%~100.1%,相对标准偏差为1.4%~9.4%。结论本研究建立的食盐中短链脂肪酸的分析方法样品制备简单,灵敏度高,回收率和稳定性好,适用于食盐中短链脂肪酸的检测。 展开更多
关键词 食盐 短链脂肪酸 顶空固相微萃取 气相色谱-质谱法
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TOPCon太阳电池及光伏组件生产过程中的废气种类及处理方法综述
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作者 刘子龙 曾鹏 +2 位作者 金双双 匡中付 方正 《太阳能》 2025年第2期82-88,共7页
隧穿氧化层钝化接触(TOPCon)太阳电池在成本及光电转换效率方面与其他硅基类太阳电池相比具有明显优势,是太阳电池领域发展的主要方向。首先详细梳理了TOPCon太阳电池及光伏组件生产过程中产生的废气种类,分析了各类废气产生的原因;然... 隧穿氧化层钝化接触(TOPCon)太阳电池在成本及光电转换效率方面与其他硅基类太阳电池相比具有明显优势,是太阳电池领域发展的主要方向。首先详细梳理了TOPCon太阳电池及光伏组件生产过程中产生的废气种类,分析了各类废气产生的原因;然后阐述了目前光伏行业常用的废气处理方法,并列举了每种处理方法的优缺点;最后分析了当前废气处理技术难点,并对未来废气处理技术的发展趋势进行了展望。研究结果表明:按工程处理的方式,TOPCon太阳电池及光伏组件生产过程中产生的废气主要可归纳为4大类,分别为等离子增强化学气相沉积(PECVD)废气、酸碱性废气、有机废气、固体粉尘。PECVD废气中的硅烷废气通常采用直燃式焚烧炉焚烧的处理方法,酸碱类废气通常采用两段式酸碱性废气净化塔进行酸碱综合回收处理,有机废气通常采用活性炭进行物理吸附处理,固体粉尘通常采用布袋除尘器进行过滤处理。未来废气处理技术将往更加高效环保、智能化、技术融合化及创新化3个方向发展。 展开更多
关键词 隧穿氧化层钝化接触太阳电池 光伏组件 生产工艺 酸碱性废气 有机废气 固体粉尘 废气处理方法
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Solid Additive-Assisted Layer-by-Layer Processing for 19%Efficiency Binary Organic Solar Cells 被引量:6
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作者 Guanyu Ding Tianyi Chen +9 位作者 Mengting Wang Xinxin Xia Chengliang He Xiangjun Zheng Yaokai Li Di Zhou Xinhui Lu Lijian Zuo Zhikang Xu Hongzheng Chen 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第7期16-29,共14页
Morphology is of great significance to the performance of organic solar cells(OSCs),since appropriate morphology could not only promote the exciton dissociation,but also reduce the charge recombination.In this work,we... Morphology is of great significance to the performance of organic solar cells(OSCs),since appropriate morphology could not only promote the exciton dissociation,but also reduce the charge recombination.In this work,we have developed a solid additive-assisted layer-by-layer(SAA-LBL)processing to fabricate high-efficiency OSCs.By adding the solid additive of fatty acid(FA)into polymer donor PM6 solution,controllable pre-phase separation forms between PM6 and FA.This intermixed morphology facilitates the diffusion of acceptor Y6 into the donor PM6 during the LBL processing,due to the good miscibility and fast-solvation of the FA with chloroform solution dripping.Interestingly,this results in the desired morphology with refined phase-separated domain and vertical phase-separation structure to better balance the charge transport/collection and exciton dissociation.Consequently,the binary single junction OSCs based on PM6:Y6 blend reach champion power conversion efficiency(PCE)of 18.16%with SAA-LBL processing,which can be generally applicable to diverse systems,e.g.,the PM6:L8-BO-based devices and thick-film devices.The efficacy of SAA-LBL is confirmed in binary OSCs based on PM6:L8-BO,where record PCEs of 19.02%and 16.44%are realized for devices with 100 and 250 nm active layers,respectively.The work provides a simple but effective way to control the morphology for high-efficiency OSCs and demonstrates the SAA-LBL processing a promising methodology for boosting the industrial manufacturing of OSCs. 展开更多
关键词 Organic solar cells Fatty acid solid additive Layer-by-layer Vertical phase separation
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Solid-state NMR studies of sulfonated SBA-15 and the synergistic catalysis of fructose into 5-hydroxymethylfurfural with dimethyl sulfoxide 被引量:2
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作者 Xin Li Wanling Shen Han Sun 《Magnetic Resonance Letters》 2022年第1期38-47,I0003,共11页
Sulfonic acid functionalized mesoporous SBA-15 was prepared using the grafting method.The structure and acid properties were comprehensively characterized using multi-nuclear and quantitative probe molecule solid-stat... Sulfonic acid functionalized mesoporous SBA-15 was prepared using the grafting method.The structure and acid properties were comprehensively characterized using multi-nuclear and quantitative probe molecule solid-state NMR(SSNMR),together with powder X-ray diffraction(XRD),scanning electron microscope(SEM),transmission electron microscopy(TEM),N2 adsorption-desorption techniques.Its catalytic performance in the conversion of fructose to 5-hydroxymethylfurfural(HMF)in dimethyl sulfoxide(DMSO)was studied.Catalyst dosage,reaction time,reaction temperature and solvent effect have been investigated.A high yield of HMF up to 93%was obtained at a relatively low temperature of 373 K for 180 min.The Brønsted acid of SBA-15_SO3H together with the solvent DMSO was found to synergistically catalyze the reaction.The catalyst preserved most of its activity after five times reuse and the catalytic activity can be recovered by H2O2 process. 展开更多
关键词 solid acid solid-state NMR Molecular sieve Heterogeneous catalysis BIOMASS
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Molecular Simulation of Naphthenic Acid Removal on Acidic Catalyst II. Experimental results of catalytic decarboxylation over acidic catalysts
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作者 Fu Xiaoqin Tian Songbai +2 位作者 Hou Shuandi Longjun Wang Xieqing 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2008年第2期29-33,共5页
The energy barriers of thermal decarboxylation reactions of petroleum acids and catalytic decarboxylation reactions of Bronsted acid and Lewis acid were analyzed using molecular simulation technology. Compared with th... The energy barriers of thermal decarboxylation reactions of petroleum acids and catalytic decarboxylation reactions of Bronsted acid and Lewis acid were analyzed using molecular simulation technology. Compared with thermal decarboxylation reactions of petroleum acids, the decarboxylation reactions by acid catalysts were easier to occur. The decarboxylaton effect by Lewis acid was better than Bronsted acid. The mechanisms of catalytic decarboxylation over acid catalyst were also verified by experiments on a fixed bed and a fluidized bed, the experimental results showed that the rate of acid removal could reach up to 97% over the acidic catalyst at a temperature above 400℃. 展开更多
关键词 petroleum acids naphthenic acid catalytic decarboxylation molecular simulation solid acidcatalyst
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植物乳杆菌固体发酵对复方中药中有效成分含量的影响 被引量:3
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作者 侯楠楠 谢全喜 +3 位作者 王俊贤 王倩 王梅 谷巍 《中国酿造》 CAS 北大核心 2024年第2期221-225,共5页
该研究采用植物乳杆菌(Lactobacillus plantarum)BLCC2-0015、BLCC2-0126和BLCC2-0410固体发酵复方中药(黄芪、甘草和益母草等),测定发酵过程中复方中药的pH、微生物数量及总酸、有机酸、粗多糖等有效成分含量的变化,评价其对复方中药... 该研究采用植物乳杆菌(Lactobacillus plantarum)BLCC2-0015、BLCC2-0126和BLCC2-0410固体发酵复方中药(黄芪、甘草和益母草等),测定发酵过程中复方中药的pH、微生物数量及总酸、有机酸、粗多糖等有效成分含量的变化,评价其对复方中药有效成分含量的影响。结果表明,植物乳杆菌发酵可降低复方中药的pH值,提高乳杆菌活菌数,抑制大肠杆菌(Escherichia coli)及霉菌的生长,并提高总酸、乳酸、苹果酸、粗多糖、阿魏酸及甘草次酸的含量。其中,植物乳杆菌BLCC2-0410发酵效果最好,发酵72 h时,复方中药的pH为4.32;乳杆菌活菌数为4.53×10^(9)CFU/g,大肠杆菌及霉菌未检出;总酸、乳酸、苹果酸、粗多糖、阿魏酸和甘草次酸含量均显著升高(P<0.05),分别为27.82 g/kg、19.25 g/kg、4.06 g/kg、5.83%、42.00 mg/kg和517.9 mg/kg。 展开更多
关键词 植物乳杆菌 复方中药 固体发酵 乳酸 阿魏酸 甘草次酸
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不同类型茄子果实主要营养成分和氨基酸含量分析 被引量:2
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作者 惠志明 张树根 +4 位作者 邓晓梅 邢永萍 张秦 王振泉 张军民 《中国蔬菜》 北大核心 2024年第3期97-103,共7页
为了解茄子果实营养品质特性,对3种类型、15个茄子DH系的果实糖度、有机酸含量、可溶性糖含量、糖酸比、可溶性固形物含量、固酸比、游离氨基酸含量进行测定分析。结果表明,3种不同类型茄子的糖度和固酸比由高到低均为紫萼紫黑圆茄>... 为了解茄子果实营养品质特性,对3种类型、15个茄子DH系的果实糖度、有机酸含量、可溶性糖含量、糖酸比、可溶性固形物含量、固酸比、游离氨基酸含量进行测定分析。结果表明,3种不同类型茄子的糖度和固酸比由高到低均为紫萼紫黑圆茄>紫萼紫黑长茄>绿萼紫黑长茄;有机酸含量为绿萼紫黑长茄>紫萼紫黑长茄>紫萼紫黑圆茄;葡萄糖、蔗糖含量均以绿萼紫黑长茄最高,果糖含量以紫萼紫黑圆茄最高;可溶性固形物含量以紫萼紫黑长茄最高;味感为鲜味、甜味的天冬氨酸、丝氨酸、甘氨酸含量由高到低均为紫萼紫黑圆茄>紫萼紫黑长茄>绿萼紫黑长茄,味感为酸甜味、苦味的天冬酰胺、精氨酸含量由高到低均为紫萼紫黑长茄>绿萼紫黑长茄>紫萼紫黑圆茄;紫萼紫黑长茄和绿萼紫黑长茄主要营养成分和游离氨基酸含量的变异度普遍高于紫萼紫黑圆茄。 展开更多
关键词 茄子 糖度 糖酸比 固酸比 游离氨基酸
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Investigation of solid-state reaction by terahertz time-domain spectroscopy
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作者 LIU Xiaohong ZHAO Hongwei WU Yuting LI Qingnuan ZHU Zhiyong 《Nuclear Science and Techniques》 SCIE CAS CSCD 2011年第3期139-143,共5页
Terahertz time-domain spectroscopy(THz-TDS)was utilized to investigate the solid-state reaction between L(+)-Tartaric acid and sodium hydrogen carbonate.Solid sodium hydrogen L(+)-tartrate monohydrate was synthesized ... Terahertz time-domain spectroscopy(THz-TDS)was utilized to investigate the solid-state reaction between L(+)-Tartaric acid and sodium hydrogen carbonate.Solid sodium hydrogen L(+)-tartrate monohydrate was synthesized efficiently by mechanical grinding,which is particularly sustainable and environmentally benign.Distinct THz absorptions were observed for pure reactants and the proposed product.The reaction process could be clearly visualized by THz spectral patterns of the reaction mixtures at different grinding time.The observed results were further confirmed by synchrotron radiation X-ray powder diffraction(SRXRPD)and Fourier transform infrared (FT-IR)spectroscopy.The study demonstrates that THz-TDS is an effective novel tool to monitor solid-state reactions in pharmaceutical industry. 展开更多
关键词 太赫兹时域光谱 固态反应 傅里叶变换红外光谱 X射线粉末衍射 碳酸氢钠 可持续发展 反应混合物 机械研磨
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基于磺化碳基固体酸的纤维素水解糖化研究进展
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作者 陆佳 苏小红 +1 位作者 刘泽 刘伟 《太阳能学报》 EI CAS CSCD 北大核心 2024年第10期663-672,共10页
对磺化碳基固体酸制备原料及制备方法进行系统介绍,分析磺化碳基固体酸物理化学结构与其催化纤维素水解的构效关系,讨论碳基固体酸失活原因及分离回收方法。针对磺化碳基固体酸与纤维素间的传质限制,总结归纳先“降结晶、再水解”的纤... 对磺化碳基固体酸制备原料及制备方法进行系统介绍,分析磺化碳基固体酸物理化学结构与其催化纤维素水解的构效关系,讨论碳基固体酸失活原因及分离回收方法。针对磺化碳基固体酸与纤维素间的传质限制,总结归纳先“降结晶、再水解”的纤维素高效水解策略。最后对磺化碳基固体酸的未来研究重点和前景进行展望,以期为促进磺化碳基固体酸在木质纤维素糖平台构建中的创新发展提供科学参考。 展开更多
关键词 生物质 水解 碳基固体酸 纤维素 糖化
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不同乳酸菌固态发酵对黑水虻幼虫营养价值的影响
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作者 郭建来 和月 +3 位作者 魏红芳 刘昆 姬向波 翟乐平 《中国饲料》 北大核心 2024年第1期155-159,共5页
本试验旨在探讨不同乳酸菌固态发酵对黑水虻幼虫中主要营养成分、pH、乳酸和多肽含量的影响,试验分为4组,分别为对照组(未发酵)、试验1组(植物乳杆菌组)、试验2组(粪肠球菌组)、试验3组(嗜酸乳杆菌组),每组3个平行。将黑水虻幼虫与麸皮... 本试验旨在探讨不同乳酸菌固态发酵对黑水虻幼虫中主要营养成分、pH、乳酸和多肽含量的影响,试验分为4组,分别为对照组(未发酵)、试验1组(植物乳杆菌组)、试验2组(粪肠球菌组)、试验3组(嗜酸乳杆菌组),每组3个平行。将黑水虻幼虫与麸皮按1:1混合,分别添加发酵用种子液,将混匀后的样品分别装入发酵袋中,放于35℃人工气候箱中发酵3 d。结果表明:与对照组相比,试验1组、2组、3组粗纤维含量均显著下降(P﹤0.05);缬氨酸含量分别增加了11.25%(P﹤0.05)、10.00%(P﹤0.05)和16.25%(P﹤0.05),脯氨酸含量分别增加了15.73%(P﹤0.05)、13.75%(P﹤0.05)和8.99%(P﹤0.05);各组之间乳酸含量差异极显著(P﹤0.01),其中试验1组乳酸含量最高,达到了8.72%;发酵后,各试验组pH显著下降(P﹤0.01),其中试验1组pH最低;发酵后3个试验组多肽含量均显著升高(P﹤0.01)。综合考虑,优先选择植物乳杆菌作为黑水虻发酵饲料发酵剂。 展开更多
关键词 乳酸菌 黑水虻幼虫 固态发酵 营养成分
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印染废水中全氟辛烷磺酸和全氟辛酸含量的液相色谱串联质谱测定
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作者 李志刚 杨宏林 《印染》 CAS 北大核心 2024年第12期66-69,共4页
建立了液相色谱串联质谱法测定纺织废水中全氟辛烷磺酸和全氟辛酸含量的方法。样品采用全自动固相萃取技术进行提取、净化和浓缩,过WAX固相萃取柱后,用2%氨水/甲醇洗脱,色谱柱为Waters ACQUITY UPLC BEH C18柱(100 mm×2.1 mm,1.7μ... 建立了液相色谱串联质谱法测定纺织废水中全氟辛烷磺酸和全氟辛酸含量的方法。样品采用全自动固相萃取技术进行提取、净化和浓缩,过WAX固相萃取柱后,用2%氨水/甲醇洗脱,色谱柱为Waters ACQUITY UPLC BEH C18柱(100 mm×2.1 mm,1.7μm),1 mmol/L乙酸铵溶液和甲醇为流动相,以电喷雾负离子MRM模式进行检测,内标法定量。全氟辛烷磺酸和全氟辛酸在0.5~50.0μg/L质量浓度范围内均具有良好的线性关系,相关系数(R)均大于0.999,方法的检出限均为0.17 ng/L,定量限均为0.5 ng/L,平均加标回收率分别为94.1%和92.8%,精密度分别为2.6%~4.2%和3.1%~6.6%。该方法具有灵敏度高、准确度好的特点,可以为印染废水的日常监测管控提供技术支撑。 展开更多
关键词 测试 液相色谱串联质谱 全自动固相萃取 全氟辛烷磺酸 全氟辛酸 印染废水
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