Tensile stress–strain and recovery behavior of Indian silk fibers and their structural dependence

The tensile stress–strain and recovery behavior of all the four commercial varieties of Indian silk fibers, namely Mulberry, Tasar, Eri, and Muga, have been studied along with their structures. Compared to the non‐Mulberry silk fibers, Mulberry silk fiber is much finer and has crystallites of smaller size, higher molecular orientation, and a more compact overall packing of molecules. These structural differences have been shown to result in (1) the presence of a distinct yield and a yield plateau in non‐Mulberry silk and their absence in Mulberry silk, and (2) relatively higher initial modulus and tenacity along with lower elongation‐to‐break and toughness and superior elstic recovery behavior of mulberry silk compared to non‐Mulberry silk. It is also observed that fine silk fibers have a relatively more ordered and compact structure with higher orientation compared to their coarse counterparts, and this gives rise to higher initial modulus and higher strength in the finer fibers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2418–2429, 2000     

Characterization of protective rust on ancient Indian iron using microprobe analyses

Local compositional and structural information was obtained from an ancient 1500-year-old Indian iron and its protective scale utilizing microprobe techniques (μXRD and μPIXE). Different locations in the iron matrix and in the entrapped slag inclusions were also analyzed for P contents. The P content of the metallic iron matrix was very heterogeneous. Lower P contents were observed in the regions near slag inclusions. The surface oxide scales was layered. Enrichment of P in the metal-scale interface and in the scale adjacent to the interface was determined. The P content in the scale decreased on moving away from the interface. Microdiffraction patterns obtained at different locations in the oxide scale indicated that at locations where the P content was high (i.e. nearer the interface), the oxide was amorphous while at locations where P was low, crystalline phases were identified. The presence of crystalline phosphates was also confirmed at some regions in the scale, where the P content was relatively very high. The probable reasons for the presence of the identified phases in the atmospheric corrosion product have been discussed.     

Evaluation of nine pesticide residues in three minor tropical fruits from southern China

The residue levels of nine pesticides (imidacloprid, acetamiprid, carbendazim, diflubenzuron, chlorbenzuron, phoxim, pyrimethanil, abamectin and iprodione) in 117 samples of three minor tropical fruits (starfruits, wax apples and Indian jujubes) from Hainan, Fujian, Guangdong and Guangxi provinces in China were analyzed using ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) after multi-residue extraction procedures. A total of 78 (66.7%) samples were positive, with residues above the limit of quantification. Indian jujube was the fruit with the highest percentage of positive samples (81.6%), followed by starfruit (61.0%) and finally wax apple (57.9%). Carbendazim was the most frequently detected residue found in 51 (43.6%) samples in the concentration ranges of 34.0–443.8 μg/kg. Diflubenzuron, phoxim, pyrimethanil and abamectin were not detected in any sample. Twenty-nine (24.8%) samples were contaminated with multiple pesticide residues, and the simultaneous occurrence of three different residues was found in one wax apple and two starfruit samples. Estimation of the potential health risks associated with the exposure to the analyzed pesticides was carried out and the estimated daily intakes (EDIs) were very low, ranging from 0.020% of the acceptable daily intakes (ADIs) for chlorbenzuron to 1.13% for carbendazim. These results indicate that despite a high occurrence of pesticides in starfruit, wax apple and Indian jujube, the contamination levels do not contribute significantly to pesticide intakes and are unlikely to have public health effects. Nevertheless, measures should be taken to hasten the registration of pesticides for use on minor fruit crops. The findings also indicate that routine monitoring of pesticide residues in minor fruits is necessary to prevent, control and reduce pesticide contamination and to minimize health risks.     

一种新的面向渔情预测的智能数据处理模型研究*

结合印度洋大眼金枪鱼渔业应用背景,提出一种新的面向渔情预测的智能数据处理模型。首先利用支持向量机（SVM）对样本数据进行训练,并运用模糊分类器对支持向量进行规则提取;然后对条件和结论分别进行可拓变换和传导变换,获得渔场动态知识。实验结果表明,获得的动态知识具有更强的解释性,对丰富渔情预测方法、解释渔场形成机制具有重要意义。     

137Cs, 239+240Pu and 240Pu/239Pu atom ratios in the surface waters of the western North Pacific Ocean, eastern Indian Ocean and their adjacent seas

Surface seawater samples were collected along the track of the R/V Hakuho-Maru cruise (KH-96-5) from Tokyo to the Southern Ocean. The (137)Cs activities were determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas, the eastern Indian Ocean, the Bay of Bengal, the Andaman Sea, and the South China Sea. The (137)Cs activities showed a wide variation with values ranging from 1.1 Bq m(-3) in the Antarctic Circumpolar Region of the Southern Ocean to 3 Bq m(-3) in the western North Pacific Ocean and the South China Sea. The latitudinal distributions of (137)Cs activity were not reflective of that of the integrated deposition density of atmospheric global fallout. The removal rates of (137)Cs from the surface waters were roughly estimated from the two data sets of Miyake et al. [Miyake Y, Saruhashi K, Sugimura Y, Kanazawa T, Hirose K. Contents of (137)Cs, plutonium and americium isotopes in the Southern Ocean waters. Pap Meteorol Geophys 1988;39:95-113] and this study to be 0.016 yr(-1) in the Sulu and Indonesian Seas, 0.033 yr(-1) in the Bay of Bengal and Andaman Sea, and 0.029 yr(-1) in the South China Sea. These values were much lower than that in the coastal surface water of the western Northwest Pacific Ocean. This was likely due to less horizontal and vertical mixing of water masses and less scavenging. (239+240)Pu activities and (240)Pu/(239)Pu atom ratios were also determined for the surface waters in the western North Pacific Ocean, the Sulu and Indonesian Seas and the South China Sea. The (240)Pu/(239)Pu atom ratios ranged from 0.199+/-0.026 to 0.248+/-0.027 on average, and were significantly higher than the global stratospheric fallout ratio of 0.18. The contributions of the North Pacific Proving Grounds close-in fallout Pu were estimated to be 20% for the western North Pacific Ocean, 39% for the Sulu and Indonesian Seas and 42% for the South China Sea by using the two end-member mixing model. The higher (240)Pu/(239)Pu atom ratios could be attributed to close-in fallout Pu delivered from the Enewetak and Bikini Atolls by ocean currents of branches of the North Equatorial Current to the Southeast Asian seas.     

Stroboscopic studies of the elastic behaviour of some Indian timbers

The dynamic Young’s modulus has been determined for eleven Indian timbers using an electronic flash lamp stroboscope to measure the frequency of vibration of the timber bars. A linear relationship is observed between Young’s modulus and the density of the timbers.     

New utilization of vegetable oils

Energy crisis and growing fuel shortage is a global concern. This phenomenon is more conspicuous in the populous, developing countries. In order to look for alternatives and extenders to the conventional fuels, studies were performed on the seed oil of some relatively unknownPutranjiva roxburghii, a plant that is abundantly available in the Indian tropical subcontinent. In a prototype experiment, the physicochemical properties of theP. roxburghii seed oil were found to be suitable for blending with diesel up to 50% without any sacrifice in performance of an internal combustion engine. Another industrially useful material, factice (vulcanized oil), was also prepared from the same oil. It was found to be suitable for blending with rubber, improving its strength, hardness, viscosity, and scorch time, and also increased its degradation temperature. This oil is not commercially traded in the market and has not yet been recommended as edible; hence industrial exploitation will not affect consumer market directly. A few more preliminary experiments indicated that the by-product oilcake is a good plant nutrient and the oil exerts profound antifungal activity. These properties need to be investigated more extensively. This plant and its oilseed deserve further attention and investigation, particularly in the tropical, coastal developing countries.     

E-Commerce in the Indian Insurance Industry: Prospects and Future

With the advent of the Internet, online processes are replacing conventional models in our society. The greatest impact in online technology has been achieved by e-commerce. E-commerce is attractive both to buyers and sellers as it reduces search costs for buyers and inventory costs for sellers. In this paper we investigate the impact of e-commerce on the insurance industry in India. The recent growth of Internet infrastructure and introduction of economic reforms in the insurance sector have opened up the monopolistic Indian insurance market to competition from foreign alliances. We study the evolving scenario in the insurance industry in India and identify the features of online insurance that improve the conventional insurance model and thus, makes it more attractive for the Indian insurance industry to go online.     

Investigating the interrelation between attitudes,learning readiness,and learning styles under virtual learning environment: a study among Indian students

ABSTRACT

Over the last few years there has been an increased emphasis on conceptualising, developing, and implementing virtual Learning initiatives across the Indian education sector. Effective and successful use of Virtual Learning Environments (VLEs) in academic setting requires identifying and solving many important social and behavioural issues. Without identifying and addressing these issues, their use can compound the mistakes of the past and leave the learner with a passive, un-engaging experience, leading to incomplete learning and low performance. Therefore, educators are required to recognise learner’s attitude, readiness, and learning style to take advantage of VLE. This study was conducted to find interrelationship of student attitude, readiness, and learning style towards the effective use of VLE. A total of 240 students who are using any form of VLE for their learning and research volunteered for the research, and the scales were filled via the convenience sampling method. The scales of learning readiness, attitude, and learning style were administered to the participants. The relationship among the variables of the research and the research hypotheses for the model were tested using different statistical tools like correlation, t-test and regression. The research result revealed that there is a correlation among learning readiness, attitude, and learning style, and each of these factors influence the effective use of VLE.