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22.
Yihua Li Wenge Yang Tuan Zhang Chaoyuan Wang Kai Wang Yonghong Hu 《Journal of solution chemistry》2013,42(12):2342-2353
Solubility data were measured for omeprazole sulfide in ethanol, 95 mass-% ethanol, ethyl acetate, isopropanol, methanol, acetone, n-butanol and n-propanol in the temperature range from 280.35 to 319.65 K by employing the gravimetric method. The solubilities increase with temperature and they are in good agreement with the calculated solubility of the modified Apelblat equation and the λh equation. The experimental solubility and correlation equation in this work can be used as essential data and model in the purification process of omeprazole sulfide. The thermodynamic properties of the solution process, including the Gibbs energy, enthalpy, and entropy were calculated using the van’t Hoff equation. 相似文献
23.
Thuan Nguyen Ngoc Ngan Nguyen Thi Kuo Ping-Chung Trinh Nguyen Thi Nu Thien Le Trung Mai Dam Sao Tuan Nguyen Ngoc Tan Le Van Thang Tran Dinh 《Chemistry of Natural Compounds》2021,57(6):1104-1106
Chemistry of Natural Compounds - 相似文献
24.
Ghassan Al-Chaar Tuan Hoang Dominick Dowds Kyle Ford Thomas Carlson Charles Marsh 《Journal of Cluster Science》2014,25(2):559-570
This study investigated the emission spectra of select silicon nanoparticles when subjected to various temperature changes. Two sizes of silicon nanoparticles, dispersed in both isopropanol and acetone solvents, were studied. Photoluminescence responses of the samples were measured in an environmental chamber that allowed exposure to temperatures in the range of ?73 to 65 °C (?100 to 150 °F). These silicon nanoparticles exhibited emission dependence on the temperature of their environment. The emission become brighter as the temperature decreased and less intense as the temperature increased. Thus, the response of these silicon nanoparticles in a harsh environment has been qualified. 相似文献
25.
Huynh Phuong Truc Tran Trinh Pham Ngoc Dinh Binh Thanh Nguyen Linh Thi Truc Truong Loan Thi Hong Tran Anh Tuan Ho Dung Manh Van Nguyen Dong 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(2):663-671
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study was to find trace elements that increase risk of breast cancer based on the deviation of the concentration of trace elements... 相似文献
26.
We report design, synthesis and evaluation of a series of naphthalenediimides (NDIs) that are bridged with short peptides. Reminiscent of peptide stapling technologies, the macrocycles are conveniently accessible by a chromogenic nucleophilic aromatic substitution of two bromides in the NDI core with two thiols from cysteine sidechains. The dimension of core‐bridged NDIs matches that of one turn of an α helix. NDI‐stapled peptides exist as two, often separable atropisomers. Introduction of tertiary amine bases in amino‐acid sidechains above the π‐acidic NDI surface affords operational anion‐π catalysts. According to an enolate chemistry benchmark reaction, anion‐π catalysis next to peptides occurs with record chemoselectivity but weak enantioselectivity. Catalytic activity drops with increasing distance of the amine base to the NDI surface, looser homocysteine bridges, mismatched, shortened and elongated α‐helix turns, and acyclic peptide controls. Elongation of isolated turns into short α helices significantly increases activity. This increase is consistent with remote control of anion‐π catalysis from the α‐helix macrodipole. 相似文献
27.
基于线阵InGaAs光电二极管阵列的光纤光栅传感解调 总被引:1,自引:0,他引:1
采用线阵InGaAs光电二极管阵列和体相位光栅并结合空分复用和波分复用技术,对光纤光栅传感进行解调.设计了基于线阵InGaAs光电二极管阵列和体相位光栅的光纤光栅传感解调系统,通过系统测试和性能分析,该解调系统解调带宽42 nm,信噪比30 dB,波长偏移测量精确度±15 pm,功率测量精确度为±0.3 dB.基于线阵InGaAs光电二极管阵列和体相位光栅的光纤光栅解调系统不但尺寸小,功耗低,而且具有较高的解调速度. 相似文献
28.
鲨鱼软骨血管形成抑制因子的分离纯化及其活性的初步研究 总被引:4,自引:0,他引:4
以广东阳江鲨鱼软骨为原料,研究了鲨鱼软骨新生血管形成抑制因子的分离纯化方法,并对其生物学活性进行了初步研究.采用盐酸胍抽提、膜超滤、丙酮分级沉淀、SephadexG-75柱层析和C4反相高效液相色谱等步骤,分离纯化出一种新的鲨鱼软骨血管生成抑制因子-a(SharkCartilageAngiogenesisInhibitor-a,SCAI-a),分子量为12600,能显著抑制鸡胚绒毛尿囊膜血管的形成. 相似文献
29.
A novel all-fiber temperature-calibrated refractometer based on a compact fiber Bragg grating(FBG) single-multi-single(SMS)structure is proposed and experimentally demonstrated.The sensor head is composed of a FBG combined with a SMS structure,in which the middle multimode fiber(MMF)section is etched by a time-controlled hydrofluoric.The transmission dip of SMS is extremely sensitive to ambient refractive index(RI)variation,whereas the upstream FBG provides the necessary temperature information for RI calibration.All aforementioned functions are performed via a compact FBG-SMS structure not longer than 25 mm.The proposed sensing device provides a linear RI sensitivity over water or waterbased solutions(RI values near 1.33 at optical wavelengths for most biological and many environmental applications),and has temperature-calibration capability.Hence,the said refractometer is a good candidate for sensing in chemical and biological applications. 相似文献
30.
We describe a method for analyzing short-pulse laser propagation through tissues for the detection of tumors and inhomogeneities in tissues with the goal of developing a time-resolved optical tomography system. Traditional methods for analyzing photon transport in tissues usually involve the parabolic or diffusion approximation, which implies infinite speed of propagation of the optical signal. To overcome such limitations we calculate the transmitted and reflected intensity distributions, using the damped-wave hyperbolic P(1) and the discrete-ordinates methods, for a wide range of laser, tissue, and tumor parameters. The results are compared with the parabolic diffusion P(1) approximation. 相似文献