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151.
Yu-Cai He Lei Gong Feng Liu Ting Lu Qing Qing Li-Qun Wang Yue Zhang Feng-Ting Gao Xi Wang 《Applied biochemistry and biotechnology》2014,173(4):894-903
In the conversion of cassava starch dregs to biogas by anaerobic fermentation, the biogas residue (BR) containing lignocellulosic materials still remained in the environment. In order to effectively utilize BR, the complexed 1-methyl-3-methylimidazolium dimethyl phosphate ([Mmim]DMP) media were used for pretreating cellulosic materials. After the optimization of pretreatment, the IL [Mmim]DMP-HCl-water (78.5:1.5:20, w/w/w) pretreament media were used for pretreating BR at 130 °C for 30 min. Furthermore, BR pretreated could be effectively saccharified by cellulase of Galactomyces sp. CCZU11-1. Moreover, BR could be used as a cheap carbon source for the production of Galactomyces sp. CCZU11-1 cellulase. After the culture optimization, the optimal culture conditions were obtained as follows: BR 5 g/L, (NH4)2SO4 5 g/L, K2HPO4 2 g/L, MgSO4 0.2 g/L, NaCl 1 g/L, PEG6000 4 g/L, pH 5.5, and culture temperature 30 °C. After the fermentation for 6 days, the FPA and CMCase were 26.2 and 52.8 U/mL, respectively. In conclusion, waste BR could be chosen as a promising feedstock for biofuels. 相似文献
152.
Chong Wu Jiang-Lin Zhao Xue-Kai Jiang Xin-Long Ni Xi Zeng Carl Redshaw Takehiko Yamato 《Analytica chimica acta》2016
A new type of chemosensor-based approach to the detection of 2,4,6-trinitrophenol (TNP) is described in this paper. Two hexahomotrioxacalix[3]arene-based chemosensors 1 and 2 were synthesized through click chemistry, which exhibited high binding affinity and selectivity toward TNP as evidenced by UV–vis and fluorescence spectroscopy studies. 1H NMR titration analysis verified that CH?O hydrogen bonding is demonstrated as the mode of interaction, which possibly facilitates effective charge-transfer. 相似文献
153.
Yan‐Tong Xu Zi‐Ming Ye Jia‐Wen Ye Li‐Ming Cao Rui‐Kang Huang Jun‐Xi Wu Dong‐Dong Zhou Xue‐Feng Zhang Chun‐Ting He Jie‐Peng Zhang Xiao‐Ming Chen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(1):145-149
Cobalt imidazolate frameworks are classical electrocatalysts for the oxygen evolution reaction (OER) but suffer from the relatively low activity. Here, a non‐3d metal modulation strategy is presented for enhancing the OER activity of cobalt imidazolate frameworks. Two isomorphous frameworks [Co4(MO4)(eim)6] (M=Mo or W, Heim=2‐ethylimidazole) having Co(eim)3(MO4) units and high water stabilities were designed and synthesized. In different neutral media, the Mo‐modulated framework coated on a glassy carbon electrode shows the best OER performances (1 mA cm?2 at an overpotential of 210 mV in CO2‐saturated 0.5 m KHCO3 electrolyte and 2/10/22 mA cm?2 at overpotential of 388/490/570 mV in phosphate buffer solution) among non‐precious metal catalysts and even outperforms RuO2. Spectroscopic measurements and computational simulations revealed that the non‐3d metals modulate the electronic structure of Co for optimum reactant/product adsorption and tailor the energy of rate‐determining step to a more moderate value. 相似文献
154.
A general and efficient synthetic method of 1,3-bis(phenylseleno)-2-propanol by reducing diphenyl diselenides with sodium borohydride in basic environment and then reacting with epichlorohydrin are described. 相似文献
155.
应用修正的BET热力学模型对Mg(NO3)2-NH4NO3-H2O三元体系和LiNO3-Mg(NO3)2-NH4NO3-H2O四元体系在273~320 K的相图进行预测,并找到一个相变温度较低的四元共晶点Mg(NO3)2.6H2O-LiNO3.3H2O-NH4NO3,其质量百分数组成为:25.5%的硝酸铵,28.4%的硝酸锂,13.8%的硝酸镁和32.3%的水,通过实验对共晶点组成材料的吸放热行为进行测定,发现其熔化温度为286.3 K,且DSC测试其相变热焓为192.7 J.g-1,表明该材料可用作潜在的低温相变储能材料。 相似文献
156.
The static polarizabilities and the second-order hyperpolarizabilities of a series of tri-nuclear metal cluster models MS4(M′PPh3)2(M′PPh3)(M=Mo,W;M′=Cu,Ag,Au)have been calculated within the first-principle theoretical framework. The model clusters have two fragments of rhombic units and it is the charge ransfer from one of these moieties to the other that is responsible for nonlinear optical property. This kind of electronic delocaization, differentiated from that of planar π-system, is very interesting and is worthy for further investigation. 相似文献
157.
158.
以3-三氯锗丙酸和正硅酸乙酯为原料,通过水解、缩聚凝胶热处理及氢气反应,在SiO2凝胶玻璃中析出立方相Ge纳米晶,当x=30时,凝胶玻璃中除了析出立方相Ge纳米晶处,还析出六方相GeO2,利用XRD测试了Ge纳米晶的大小,发现随着掺杂量的增加,纳米颗粒粒径从1nm增大到10nm,电子衍射表明镶嵌在SiO2凝交玻璃中的Ge纳米晶为多晶结构。 相似文献
159.
对噬菌体展示人单链抗体库进行筛选,得到与半抗原S-二硝基苯取代的谷胱甘肽二丁酯特异结合的单链抗体3B10。用计算机模拟分析了单链抗体的空间结构,发现抗原结合的CDR3区位于抗体的表面,推测其可能进一步参加硒化反。利用突变引物,在大肠杆菌中表达了可溶性抗体蛋白,并用化学方法将催化必需基团硒代半胱氨酸(Sec)组装到3B10抗原结合部位,获得了具有谷胱甘肽过氧化酶活力的人源抗体酶。动力学研究结果表明,抗体酶和天然酶一样,符合乒乓反应机制。 相似文献
160.
利用稳态和瞬态光谱方法研究了不同铕离子发光体系中各种因素对铕离子发光性质的影响.通过吸收和激发光谱的变化分析了稀土离子Gd3+对Eu3+增敏机理,并从荧光衰减动力学角度证明了主配体噻吩甲酰三氟丙酮(TTA)、协配体邻啡咯啉(Phen)、稀土离子Gd3+和表面活性剂TX-100对铕离子发光的增敏作用.4种发光体系Eu3+/Gd3+/TTA/Phen/TX-100,Eu3+/TTA/Phen/TX-100,Eu3+/Gd3+/TTA/Phen和Eu3+/Gd3+/TTA/TX-100中铕离子5D0态的发光寿命依次为980>670>400>260μs,而且存在铕离子5D1到5D0的传能过程.在发光越强的体系中,5D1的衰减越慢,相应地5D0的上升时间也就越长.研究结果表明,在最佳发光体系中既存在分子内的能量转移,又存在分子间的能量传递. 相似文献