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1.
Polyoxyethyleneglycol (PEG-600) monoesters of undecylenic, lauric, myristic, palmitic, stearic, oleic, ricinoleic and 12-hydroxystearic acids were prepared in 80-85% yield by reacting PEG with boric acid, esterifying the resultant borate with fatty acid, and selectively hydrolyzing the borate ester; their surface active properties were evaluated. Increase in acyl chain length increased the surface tension. The presence of a double bond or hydroxyl group in C18 series improved the wetting and emulsifying proper-ties. Unsaturation in the fatty acid chain reduced the foaming power.  相似文献   
2.
In wireless sensor and actor network research, the commonly used mobility models for a mobile actor are random walk model, random waypoint mobility model, or variants thereof. For a fully connected network, the choice of mobility model for the actor is not critical because, there is at least one assured path from the sensor nodes to the actor node. But, for a sparsely connected network where information cannot propagate beyond a cluster, random movement of the actor may not be the best choice to maximize event detection and subsequent action. This paper presents static and dynamic intelligent mobility models that are based on the inherent clusters’ information of a sparsely connected network. Simulation results validate the idea behind the intelligent mobility models and provide insights into the applicability of these mobility models in different application scenarios.  相似文献   
3.
汽车电子应用不断增多,从驾驶室娱乐、安全气囊、ABS到发动机.它们各自由于在车内位置不同而要求不同,由此对工作温度、过程电压和可靠性提出了多种要求.  相似文献   
4.
5.
Indian wood apple seed (Feronia elephantum Correa) constituting 6% (dry weight basis) of the fruit, contains 34% oil and 28% protein. The kernel comprises 62% of the seed. The oil is yellow with an iodine value 131, saponification value 192, unsaponifiable matter 1%. Fatty acid profile of oil by GLC is: palmitic 19.3, stearic 7.3, oleic 27.2, linoleic 19.8 and linolenic 26.4%.  相似文献   
6.
The rise in global sourcing has led to extended supply chains. Extended supply chains generally have more mode changes, border crossings, rail classification yards, port congestion and so forth, that all lead to more delivery disruption risk. To test this assertion, we perform an empirical assessment of the inbound supply chain disruption risk at a major manufacturer that imports components from over three dozen different countries. Although delivery disruption risk can be mitigated with effort, we observe that delivery disruption risk increases with distance. Based on industrial data, we quantify the increase in delivery disruption with international versus domestic suppliers and intercontinental versus continental suppliers.  相似文献   
7.
The mixed convection of a nanofluid flow past an inclined wavy surface in the existence of gyrotactic microbes is considered. To convert the wavy surface to a plane surface, a transformation of coordinates is applied. The governing equations that are nonlinear and the accompanying boundary conditions are converted into a dimensionless form using pseudo-similarity variables. Using a local linearization process, the system of nonlinear partial differential equations is linearized. The resulting system is solved using the Bivariate Chebyshev pseudo-spectral collocation method. The influence of different physical and geometrical factors on the parameters of engineering importance of the flow is analyzed and illustrated graphically. It is observed that the skin friction, the density of motile microorganisms, and nanoparticle mass transfer rate are increasing with an increase in the bioconvection Peclet and Schmidt numbers whereas these quantities are decreasing with an increase in Rayleigh number. The local Nusselt number, nanoparticle Sherwood number, and density number of microbes increases with an increase in the Brownian motion and thermophoresis parameter. These physical quantities are increasing when the surface changes from horizontal to vertical.  相似文献   
8.
Sajid Husain  K. Sita Devi 《Lipids》1993,28(11):1037-1040
A simple, high-performance liquid chromatographic method is described for the separation of tetraenoic, trienoic and dienoic conjugated fatty acids on a Zorbax ODS reversed-phase column using acetonitrile/tetrahydrofuran (95∶5, vol/vol) at a flow rate of 1.2 mL/min as mobile phase. Also described is the separation of the isomeric conjugated fatty acids with acetonitrile/water/tetrahydrofuran (90∶90∶1, by vol) as mobile phase. The simultaneous detection and identification of the separated geometrical isomers in the eluant was accomplished using photodiode array detection.  相似文献   
9.
Gradually increasing temperatures at global and local scales are causing heat stress for cool and summer-season food legumes, such as lentil (Lens culinaris Medik.), which is highly susceptible to heat stress, especially during its reproductive stages of development. Hence, suitable strategies are needed to develop heat tolerance in this legume. In the present study, we tested the effectiveness of heat priming (HPr; 6 h at 35 °C) the lentil seeds and a foliar treatment of γ-aminobutyric acid (GABA; 1 mM; applied twice at different times), singly or in combination (HPr+GABA), under heat stress (32/20 °C) in two heat-tolerant (HT; IG2507, IG3263) and two heat-sensitive (HS; IG2821, IG2849) genotypes to mitigate heat stress. The three treatments significantly reduced heat injury to leaves and flowers, particularly when applied in combination, including leaf damage assessed as membrane injury, cellular oxidizing ability, leaf water status, and stomatal conductance. The combined HPr+GABA treatment significantly improved the photosynthetic function, measured as photosynthetic efficiency, chlorophyll concentration, and sucrose synthesis; and significantly reduced the oxidative damage, which was associated with a marked up-regulation in the activities of enzymatic antioxidants. The combined treatment also facilitated the synthesis of osmolytes, such as proline and glycine betaine, by upregulating the expression of their biosynthesizing enzymes (pyrroline-5-carboxylate synthase; betaine aldehyde dehydrogenase) under heat stress. The HPr+GABA treatment caused a considerable enhancement in endogenous levels of GABA in leaves, more so in the two heat-sensitive genotypes. The reproductive function, measured as germination and viability of pollen grains, receptivity of stigma, and viability of ovules, was significantly improved with combined treatment, resulting in enhanced pod number (21–23% in HT and 35–38% in HS genotypes, compared to heat stress alone) and seed yield per plant (22–24% in HT and 37–40% in HS genotypes, in comparison to heat stress alone). The combined treatment (HPr+GABA) was more effective and pronounced in heat-sensitive than heat-tolerant genotypes for all the traits tested. This study offers a potential solution for tackling and protecting heat stress injury in lentil plants.  相似文献   
10.
Genome-wide association studies (GWAS) have been successful in the identification of the several urinary bladder cancer (UBC) susceptibility loci, pointing towards novel genes involved in tumor development. Despite that, functional characterization of the identified variants remains challenging, as they mostly map to poorly understood, non-coding regions. Recently, two of the UBC risk variants (PSCA and UGT1A) were confirmed to have functional consequences. They were shown to modify bladder cancer risk by influencing gene expression in an allele-specific manner. Although the role of the other UBC risk variants is unknown, it can be hypothesized—based on studies from different cancer types—that they influence cancer susceptibility by alterations in regulatory networks. The insight into UBC heritability gained through GWAS and further functional studies can impact on cancer prevention and screening, as well as on the development of new biomarkers and future personalized therapies.  相似文献   
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