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71.
Strontium concentration and isotopic data for subsurface flowing groundwaters of the Ganges-Brahmaputra (G-B) delta in the Bengal Basin demonstrate that this is a potentially significant source of strontium to the oceans, equal in magnitude to the dissolved strontium concentration carried to the oceans by the G-B river waters. The strontium concentrations of groundwaters are higher by a factor of about 10 than typical G-B river waters and they have similar 87Sr/86Sr ratio to the river waters. These new data suggest that the present contribution of the G-B system to the rise in 87Sr/86Sr ratio in seawater is higher by at least a factor of 2 to 5 than the average over the past 40 million years.  相似文献   
72.
From early times, jute fibre has been generally conditioned for easy spinning by adding oil and water in the form of an emulsion. The commonly used oil consists of C12–C31 fractions of mineral oil that sometimes impart different intensities of oily (kerosene) or fishy smell to the end product. In the present work, efforts have been made to find a suitable sustainable substitute of mineral oil based conditioning agent for spinning of jute yarn and for this, three types of vegetable oil (rice bran oil, palmolein oil and castor oil), a silicone emulsion, a mixed enzyme system and glycerine have been used separately or in combinations as conditioning agents for jute fibre before its mechanical processing for making yarn in jute spinning machines. Considering comparable mechanical process performance for spinning of jute fibre (viz., fibre loss as droppings during processing, moisture retention prior to spinning stage and spinning end breakage rate), tensile properties of yarn, and lower yarn hairiness, it may be suggested to use 2.5% castor oil alone, or 2% castor oil in combination with 0.1–0.5% glycerine in the form of oil-in-water emulsion as the most suitable alternatives to conventional mineral oil-based jute conditioning agent to spin ordinary jute yarn.  相似文献   
73.
Coconut fibres were subjected to chemical treatment to obtain softer and finer fibres, suitable to blend with other finer fibre like jute. The chemical softening recipe was optimized using Box-Behnken design of experiments as 40 % Na2S, 10 % NaOH and 6 % Na2CO3, which notably reduced the fineness (33 %) and flexural rigidity (74 %) and improved tensile property of coconut fibre. Effect of softening of coconut fibre on its process performance was studied in high speed mechanized spinning system at different blend ratios with jute. Blending with jute assists in spinning of coconut fibre to produce yarn of 520 tex at production rate of 5-6 kg/h, as compared to 15 kg/day for hand spun 5300 tex raw coconut fibre yarn in manual system. Analysis of blended yarn structure in terms of packing density, radial distribution of fiber components (SEM) and mass irregularity were investigated. SEM shows yarns made from softened coconut fibre -jute blends are more compact than raw coconut fibre -jute blend yarns. Coconut fibres were preferentially migrated to core of the yarn. Major yarn properties viz., tensile strength, and flexural rigidity of raw and chemically softened blended yarns were compared against their finest possible 100 % coconut fibre yarn properties. Yarn made up to 50:50 chemically softened coconut fibre-jute blend showed much better spinning performance, and having superior property in terms of reduced diameter, higher compactness, strength, initial modulus and less flexural rigidity than 100 % raw, 100 % chemically softened coconut fibre rope, and raw coconut fibre-jute blend yarns.  相似文献   
74.
Temperatures of equilibration for the majority (81 percent) of the eclogite xenoliths of the Roberts Victor kimberlite pipe in South Africa range between 1000 degrees and 1250 degrees C, falling essentially on the gap of the lower limb of the subcontinental inflected geotherm derived from garnet peridotite xenoliths. In view of the Archean age (>2.6 x 10(9) years) of these eclogites and their stratigraphic position on the geotherm, it is proposed that the inflected part of the geotherm represents the convective boundary layer beneath the conductive lid of the lithospheric plate. The gradient of 8 Celsius degrees per kilometer for the inflection is characteristic of a double thermal boundary layer and suggests layered convection rather than whole mantle convection for the earth.  相似文献   
75.
刘奇  谢甫绨  谢志涛 《大豆科学》2007,26(2):154-157
以辽宁20年代、辽宁当代以及与辽宁近纬度的美国俄亥俄州当代育成的亚有限结荚习性大豆品种各4个为试材,研究了不同来源大豆品种籽粒品质的差异,以及不同磷酸二铵施肥水平对大豆籽粒品质的影响.结果表明:就试验采用的品种而言,俄亥俄州立大学更注重籽粒脂肪含量的改良,而且遗传获得较大,而辽宁省育成的新品种其脂肪含量也比老品种稍高一些,蛋白质含量则有所下降.就品种来说,老品种Mukden的品质最好,蛋脂总含量高达64.7%,辽宁新品种中辽豆12号最好,俄亥俄新品种中OhioFG1最好.蛋白质含量以Mukden含量最高,达44.85%,脂肪含量以Darby含量最高,为21.39%.与不施肥相比,150 kg/hm2、300 kg/hm2磷酸二铵施肥处理会使各品种的蛋白质含量得到提高,脂肪含量有所降低,从不同来源品种组平均值来看,施用磷酸二铵300 kg/hm2的处理,大豆籽粒的蛋白质含量高于150 kg/hm2处理,脂肪含量则与之相反.  相似文献   
76.
A detailed study of electromagnetic shielding effectiveness (EMSE) of woven fabrics made of polyester and stainless steel/polyester blended conductive yarn was presented in this research work. Fabrics with different structures were analyzed and their shielding behavior was reported under different frequencies. Shielding efficiency of fabric was analyzed by vector network analyzer in the frequency range of 300 kHz to 1.5 GHz using coaxial transmission line holder. The effects of different fabric parameters such as weft density, proportion of conductive weft yarn, proportion of stainless steel content, grid openness, weave pattern and number of fabric layers on EMSE of fabrics were studied. The EMSE of fabric was found to be increased with increase in proportion of conductive yarn in the weft way. With increase in overall stainless-steel content in the fabric, the EMSE of fabric was increased. As such weave is considered, it did not have significant effect on EMSE of fabrics. But fabric with lower openness and aperture ratio showed better conducting network, hence better shielding. With increase in number of layers of fabric and ply yarns, EMSE of fabric was increased.  相似文献   
77.
In lower eukaryotes-like fish, innate immunity contributed by various pattern recognition receptor (PRR) plays an essential role in protection against diseases. Nucleotide-binding and oligomerization domain (NOD)-2 is a cytoplasmic PRR that recognizes MDP (muramyl dipeptide) of the Gram positive and Gram negative bacteria as ligand and activates signalling to induce innate immunity. Hypothesizing a similar NOD2 signalling pathway of higher eukaryotes, the peripheral blood leucocytes (PBLs) of rohu (Labeo rohita) was stimulated with MDP. The data of quantitative real-time PCR (qRT-PCR) revealed MDP-mediated inductive expression of NOD2 and its down-stream molecule RICK/RIP2 (receptor-interacting serine-threonine protein kinase-2). This observation suggested the existence of MDP-binding sites in rohu NOD2 (rNOD2). To investigate it, 3D model of ligand-binding leucine-rich repeat (LRR) region of rNOD2 (rNOD2-LRR) was constructed following ab initio and threading approaches in I-TASSER web server. Structural refinement of the model was performed by energy minimization, and MD (molecular dynamics) simulation was performed in GROMACS (Groningen Machine for Chemical Simulations). The refined model of rNOD2-LRR was validated through SAVES, ProSA, ProQ, WHAT IF and MolProbity servers, and molecular docking with MDP was carried out in GOLD 4.1. The result of docking identified LRR3-7 comprising Lys820, Phe821, Asn822, Arg847, Gly849, Trp877, Trp901 and Trp931 as MDP-binding critical amino acids in rNOD2. This is the first study in fish to provide an insight into the 3D structure of NOD2-LRR region and its important motifs that are expected to be engaged in MDP binding and innate immunity.  相似文献   
78.
79.
Gibberellin (GA), benzyladenine (BA), and maleic hydrazide (MH) promoted formation of female flowers in Momordica charantia L. GA was most effective. Low concentration of 2-chloroethyl trimethyl ammonium chloride (CCC) showed femineity, whereas high concentration showed a masculinizing effect. The effects of different concentrations of GA, BA, MH and CCC on flowering and sex expression are discussed. GA should not be considered as a general male sex hormone for all cucurbits.  相似文献   
80.
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