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51.
In this study, wheat gluten fibers loaded by the azathioprine were fabricated and their physicochemical properties were studied. The nanofibers were characterized by using the scanning electron microscopy (SEM), Fourier transformed-infrared spectroscopy, X-ray diffractometry, thermogravimetric, and differential thermal analysis. The SEM images showed that the addition of polyvinyl alcohol decreased the fibers’ diameters. The diameters of 77.14?±?14.11?nm were obtained for the wheat gluten–polyvinyl alcohol loaded drug fibers. In addition, the cell viability evaluation conducted by the MTT assay proved no cytotoxicity of the prepared nonofibers at concentrations up to 4?mg/mL to human umbilical vein endothelial cell. 相似文献
52.
彭家寅 《计算机工程与应用》2020,56(12):93-97
目的是利用高维量子纠缠态为量子信道,讨论未知单粒子态的受控隐形传输问题。以三维量子纠缠态为信道,提出一个二维任意单粒子态的受控隐形传输协议。提出了以任意[d]-维量子纠缠态为量子信道,[t]-维任意单粒子态的隐形传输协议[(t相似文献
53.
Yun-Ting Tsai Yi Yang Hao-Chun Huang Chi-Min Shu 《American Institute of Chemical Engineers》2020,66(5):e16888
Three types of self-prepared chemical dust suppressants (CDSs) were investigated for their inhibitory effects on nitrocellulose (NC) cloud dust explosion. The results revealed that NC is extremely sensitive to electric sparks and has a high explosion intensity. CaCl2-CDS effectively increased the particle size to control fly dust substantially inhibiting dust cloud explosions. However, both Na2SO4-CDS and MgCl2-CDS exhibited poor abilities and even promoted explosion. Therefore, neither Na2SO4-CDS nor MgCl2-CDS is recommended as a CDS for NC. Inappropriately using CDSs may engender severe explosions. Furthermore, a mechanism underlying NC dust cloud combustion and explosion was proposed. NC has three stages of heat release: autoxidation, thermal decomposition, and combustion. Thermal decomposition, combustion, and explosion were triggered depending on the energy provided from autoxidation. CaCl2-CDS inhibited only combustion. This study reveals the mechanism underlying NC dust cloud explosions and provides useful information for the development of more optimized CDSs. 相似文献
54.
55.
沙垒田凸起地区是渤海海域西部新近系油气最为富集的区域,为了明确新近系走滑断裂发育特征及对油气富集的控制作用,依托连片高精度三维地震、钻井取心等资料,对走滑断裂类型及发育特征进行了详细刻画,并对走滑断裂与成藏要素之间的关系进行了探讨。综合研究表明:研究区发育断穿基底走滑断裂、盖层走滑断裂及伸展-走滑断裂三种不同类型走滑断裂;走滑断裂对圈闭的控制作用表现为在不同类型走滑断裂控制下,断裂带内及断裂带间形成了多种类型圈闭,其中大型披覆背斜圈闭、断鼻、断背斜圈闭为有利圈闭,小型断块圈闭为不利圈闭;走滑断裂对输导体系的控制作用体现在断裂活动控制了骨架砂体输导体系及断裂输导体系的形成发育,有利于周边凹陷成熟烃源岩排烃及运移输导;走滑断裂对储层的控制作用表现为走滑作用形成的高角度裂缝提高了储层渗透率,改善了储层物性。新近纪普遍发育的走滑断裂是研究区油气富集的主控因素。 相似文献
56.
Alexandros G. Venetsanos 《International Journal of Hydrogen Energy》2018,43(50):22715-22726
The estimation of the release conditions is critical input to subsequent risk assessment accident analysis. To this respect a new homogeneous non-equilibrium two-phase model is proposed to simulate the depressurization from stagnation conditions leading to the bubbly flow regime. The proposed model, being intermediate between HEM (homogeneous equilibrium) and HFM (homogeneous frozen) models, presents no discontinuity in the liquid phase depressurization path gradient and therefore no discontinuity in sound speed. The proposed model is successfully validated against the NASA hydrogen critical flow experiments and compared against predictions from both HEM and HFM, using hydrogen physical properties from NIST. An increase of the pressure difference between stagnation and the intersection of isentropic with saturation line leads to increase of the choked mass flux, decrease of the throat to stagnation pressure ratio, decrease of the liquid superheat and decrease of the vapor quality. The proposed model was found to overestimate the experimental throat mass fluxes by no more than 10% and underestimate the experimental throat to stagnation pressure ratios by no more than 50%, while predicted liquid superheat values range from 3.8 to 11% of the saturation temperature. Deviations between models were found to increase for low values of the pressure difference parameter, where non-equilibrium effects become more important. Under these conditions the throat mass flux is underestimated by maximum 20% by HEM and overestimated up to 32% by HFM, while the throat to stagnation pressure ratio is overestimated by up to 72% and underestimated by 80% respectively. 相似文献
57.
Hao Dong Jiapeng He Kaijun Xiao Chao Li 《International Journal of Food Science & Technology》2020,55(1):293-302
Temperature-sensitive polyurethane (TSPU) films incorporated with carvacrol and cinnamyl aldehyde were prepared for the potential use of food packaging. The antimicrobial properties and sustained release kinetics of carvacrol and cinnamyl aldehyde in TSPU film were investigated. Results indicated that cinnamyl aldehyde and carvacrol had favourable antimicrobial properties at relatively low addition ratio. The diffusion and release of carvacrol were linearly related to temperature and its addition ratio. The release rates of carvacrol from TSPU film increased from 0.6% to 2.2% with the increase of addition ratio and temperature. The first-order kinetic equation could be used to describe its diffusion and sustained release process. TSPU films could significantly prolong the shelf life of Cantonese-style moon cakes by effectively inhibiting microbial growth and decreasing lipid oxidation comparing with commonly used polyethylene food packaging. Results obtained in the present work can provide technical guide of sustained release food packaging films with antimicrobial properties. 相似文献
58.
59.
Sofia Grizopoulou Maria Karagiorgou Vassilis Karageorgiou Ping Shao Dimitrios Petridis Christos Ritzoulis 《Journal of the American Oil Chemists' Society》2020,97(3):243-252
Spontaneously foaming oil systems have been formulated from water-in-oil emulsions by the controlled release and entrapment of gas in emulsified water droplets contained within the oil. The cascade of events leading to their formation is as follows: Two Span 60-emulsified populations of water droplets, one containing Na2CO3, the other 10% HCl and caseinate, were mixed in miglyol oil; the controlled coalescence of Na2CO3 droplets with the HCl ones served as a microreactor for the pH reduction and the subsequent release of CO2 from Na2CO3; these gas microbubbles were arrested by sodium caseinate, stabilizing a microfoam within the water droplets; these droplets expanded under the rising gas pressure, spontaneously transforming the surrounding oil into a foamy oleogel containing water droplets. 相似文献
60.
Xing Qin Prof. Yongsheng Li 《Chembiochem : a European journal of chemical biology》2020,21(9):1236-1253
The emergence and development of nanomedicine have alleviated problems existing in traditional chemotherapy drugs, such as short lifetime, concomitant side effects, and weak tumor-targeting capability. Nevertheless, the further applications of drug-loaded nanocarriers are still limited by their premature leakage, weak targeting capability, and insufficient intracellular release. In past decades, various nanocarriers, including gold nanoparticles, porous silica nanoparticles, carbon-based nanoparticles, micelles, liposomes, and polymer–drug conjugates, have been intensively investigated for tumor therapy. Among these, polymer-based nanocarriers have attracted more attention due to their biocompatibilities and capability of being modified for stimuli-responsive drug release. In this review, three popular strategies to design and synthesize polymer-based stimuli-responsive nanocarriers are discussed. The discussion goes from stimuli-responsive polymers with responsive backbones or modified by responsive functional groups for drug encapsulation and release to polymer–drug conjugates with responsive covalent linkages. In particular, due to the facile synthetic processes and mild reaction conditions for crosslinked structures, the latest progress in responsive crosslinked structures is emphasized. Finally, future perspectives for these nanomaterials are given, which are expected to provide inspiration for researchers to design more effective and safer tumor-killing nanomedicines. 相似文献