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51.
The ability of low cost bio‐adsorbent sawdust to remove basic dye (methylene blue) from aqueous solution is investigated using it in two different forms: in raw form and in chemically treated (with sulphuric acid) form. The effect of contact time, dye concentration, adsorbent dose and the kinetics of adsorption were studied in batch experiments. At neutral pH and 4?gm/l of chemically activated and raw sawdust adsorbents, removal of 98.12% and 97.18% of methylene blue dye (at 100?mg/l concentration) from the aqueous solution, was the best result obtained during study. An average percentage removal difference of less than 5%, between two adsorbents was achieved under different conditions in the experiments. The data fit well in Freundlich isotherm.  相似文献   
52.
With the growing energy demands in India and its neighboring countries, Iran–Pakistan–India (IPI) gas pipeline assumes special significance. Energy-deficient countries such as India, China, and Pakistan are vying to acquire gas fields in different parts of the world. This has led to two conspicuous developments: first, they are competing against each other and secondly, a situation is emerging where they might have to confront the US and the western countries in the near future in their attempt to control energy bases. The proposed IPI pipeline is an attempt to acquire such base. However, Pakistan is playing its own game to maximize its leverages. Pakistan, which refuses to establish even normal trading ties with India, craves to earn hundreds of millions of dollars in transit fees and other annual royalties from a gas pipeline which runs from Iran's South Pars fields to Barmer in western India. Pakistan promises to subsidize its gas imports from Iran and thus also become a major forex earner. It is willing to give pipeline related ‘international guarantees’ notwithstanding its record of covert actions in breach of international law (such as the export of terrorism) and its reluctance to reciprocally provide India what World Trade Organization (WTO) rules obligate it to do—Most Favored Nation (MFN) status. India is looking at the possibility of using some set of norms for securing gas supply through pipeline as the European Union has already initiated a discussion on the issue. The key point that is relevant to India's plan to build a pipeline to source gas from Iran relates to national treatment for pipeline. Under the principle of national treatment which also figures in relation to foreign direct investment (FDI), the country through which a pipeline transits should provide some level of security to the transiting pipeline as it would have provided to its domestic pipelines. This paper will endeavor to analyze, first, the significance of this pipeline for India and then the geopolitics involved in it.  相似文献   
53.
The effect of copper on the annealing behaviour of interstitial free (IF) steel has been investigated using thermoelectric power (TEP) and resistivity measurements. Kinetics of annealing of cold rolled copper-containing IF steel was found to be sluggish when compared with the base steels. TEP measurement revealed that copper has a negative coefficient of TEP in α-iron.  相似文献   
54.
A new approach based on iteration is presented to extract the amount and composition of bainitic ferrite and austenite from the dilatation curve. The carbon concentration of bainitic ferrite estimated from the dilatation curve was found to be higher than the solubility of carbon in α-ferrite that is in paraequilibrium with γ-austenite, and it agreed well with the corresponding value estimated from X-ray diffraction (XRD). A slightly better fit between the experimental and calculated dilatation curves was obtained with body-centered-tetragonal than with body-centered-cubic (bcc) bainitic ferrite. These results suggest that the austenite to bainitic ferrite transformation occurs through a displacive mechanism.  相似文献   
55.
56.
Bufalin and other cardiac steroids (CS) have been used for centuries for the treatment of congestive heart failure, arrhythmias, and other maladies. However, toxicity and the small therapeutic window of this family of steroids limit their use. Therefore, attempts to synthesize a potent, but less toxic, CS are of major importance. In the present study, two novel bufalin derivatives were synthesized and some of their pharmacological properties were characterized. The reaction of bufalin with Ishikawa’s reagent resulted in the production of two novel bufalin derivatives: bufalin 2,3-ene and bufalin 3,4-ene. The compounds were purified with TLC and HPLC and their structure was verified with UV, NMR, and MS analyses. The biological activities of these compounds were evaluated by testing their ability to inhibit the Na+, K+-ATPase activity of the brain microsomal fraction to induce cytotoxic activity against the NCI-60 human tumor cell line panel and non-cancer human cells, and to increase the force of contraction of quail embryonic heart muscle cells in culture. The two steroids exhibited biological activities similar to those of other CS in the tested experimental systems, but with reduced cytotoxicity, advocating their development as drugs for the treatment of heart failure and arrhythmias.  相似文献   
57.
A study was conducted to evaluate the performance of locally available electric arc furnace slag (EAFS) as a substrate for removing phosphorus from wastewater. First, in a laboratory study, EAFS was found to have high phosphorus removal efficiency for three P concentrations (0.3, 3.0, and 6.0 mg/L); this resulted in nearly 100% phosphorus removal in 24 h. Next, the experiment was repeated using aeration and similar phosphorus removal was observed but in a shorter contact time of 1 h. The adsorption capacity of EAFS was determined to be 1,458 mg/kg. In a pilot-scale study, over 90% P removal took place in the first 4 h under nonaerated conditions, and nearly 100% removal in 8 h. While the P removal with aeration was relatively less initially for the shorter residence times, a 100% removal was observed for the 24-h residence time.  相似文献   
58.
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   
59.
Metallurgical and Materials Transactions A - The present study investigates the orientation dependence of deformation-induced martensite (DIM) transformation in carbide-free bainitic steel using...  相似文献   
60.
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