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Mobile Source Air Toxics (MSAT) II regulations restrict the average benzene level in gasoline sold in the U.S. to 0.62 vol%. In India and in several other countries, benzene in [...]

This manuscript research presents the design of steel building and analysis of different damper and base isolation systems at various seismic zone for a multi-storied steel framed building. Steel buildings are easy to build and gives more strength, also after demolish there are scrap value so ties more economical. Base isolation provides structural safety and also safety and security for people and properties in the building. Base isolation is also used for the retrofit of the historic buildings. In the present manuscript work done on, Seismic analysis of G + 10 multi storied steel building with and without dampers (viscous damper and friction damper) and base isolation system (friction isolation and lead plug bearing). In this types of seismic provision which one is more suitable according to seismic zone for stabilization of steel building analyzed. In this work used seismic zone II, zone III, zone IV and zone V by using ETABs software analysis carried out. Found the optimum damper and base isolation combination effect in the steel building and analysis result of seismic responses (viz. storey drift, storey displacement, base shear).

Thoroughly calibrated and validated DSSAT–CERES sorghum model’s seasonal analysis tool was used to evaluate the sensitivity of four kharifsorghum cultivars across three dates of sowing to changes in temperature. Five temperature scenarios (no change in temp, +?0.5 °C, +?1 °C, +?1.5 °C and +?2 °C) were created using 32 years’ observed past weather data (1985–2016). The model was run for all four cultivars across three dates of sowing under standard package of practices recommended to Northern Transition Zone of Karnataka for 32 years under rainfed conditions. Average of 32 years’ model simulated outputs revealed that kharifsorghum yield is sensitive to changes in temperature. Among the genotypes tested, CSH-16 gave the highest grain yield in all temperature scenarios across dates of sowing, and was followed by CSV-17, CSV-23 and CSH-23. Among the dates of sowing, across all temperature scenarios, early sowing (15th June) gave the highest grain yield as compared to later sowings (i.e., 30th June and 15th July of 2011 and 2012). Among the cultivars tested, irrespective of dates of sowing, for every 0.5 °C increase in temperature, the average yield reduction was found to be the highest in CSV-23 (9.39%), followed by CSV-16 (7.51%), CSH-23 (7.26%) and CSV-17 (7.25%), which shows the differential response among cultivars to rise in temperature. This study indicates that as part of adaptation to future climates manipulation in sowing date as well as choice of heat tolerant cultivars would be required.

This manuscript review presents the design of steel building and analysis of different damper and base isolation systems at various seismic zone for a multi-storied steel framed building. Steel buildings are easy to build and have more strength; also after demolishment, there is value for the scraps, so it is more economical. Base isolation provides structural safety and also safety and security for people and properties in the building. Base isolation is also used for the retrofit of the historic buildings. In this study, seismic analysis of G + 10 multi-storied steel building with and without dampers (viscous damper and friction damper) and base isolation system (friction isolation and lead plug bearing) is done. These types of seismic provision are used many more times but which one is suitable according to seismic zone for stabilization of steel building will be analyzed in this review. In this work, study of seismic zone II, zone III, zone IV, and zone V using ETABs software analysis will be carried out. The optimum damper and base isolation combination effect in the steel building will be studied and result of responses will be analyzed (viz. storey drift, storey displacement, base shear).

Computational model based on extended isogeometric analysis is implemented for the fracture analysis of functionally graded material (FGM) reinforced with multi-walled carbon nanotube (MWCNT), i.e., FGM-MWCNT structure under mechanical and thermo-mechanical loading conditions. The FGM body taken for the study is composed of metal (Ti–6Al–4V) on the left side and ceramic (ZiO2) on right side. For the gradation of FGM properties that change throughout the domain length, exponential law is assumed. Moreover, the FGM is reinforced with 0–5% of MWCNT to obtain FGM-MWCNT composite. In order to perform this fracture analysis, first the equivalent mechanical and thermal properties of the FGM-MWCNT composite are evaluated using some of the micromechanics models cited in the literature. Using the interaction integral approach, SIFs are extracted. The results of the test show that when the volume percentage of MWCNTs increases, it enhances the failure resistance of the composite.

ABSTRACTIn this paper the effect of incremental rise of tyre pyrolysis oil in the blend is analyzed to explore the performance and emission parameters of a single cylinder VCR diesel engine. During experimentation proportion of TPO were 10, 25, 35, 50, 60, 75 and 90 % with diesel fuel. Tests were conducted using four different loading conditions. The experiments were performed using an analytical tool known as Design of Experiments on the basis of Response Surface Methodology. The conclusive models of the RSM prepared to predict the response criterion such as BSFC, BTE, CO, nitrogen oxides, smoke and Mechanical efficiency. The results depicted that with rise in the load, BSFC decrease while it increases with rise in TPO proportion and found lower at 50% TPO and increases again above 50% TPO. BTE increased with increase in the load and found to be highest at higher TPO. For all blends, an increase in Nitrogen oxides found with increase in load and TPO proportion. Parameter optimization executed using the desirability approach method of the RSM for improved conduct and reduced emissions. A load of 4.57 kg (61.7567%) and 40.94% TPO in the blend are suggested as the optimal criterion for the test engine.

The long-term (2000–2015) MODIS EOS-Terra/Aqua multi-algorithm (DT, DB and combined DTB) retrieved AOD550 nmand AERONET measured AOD550 nmdata at Gandhi College (24.87° N, 84.19° E; 60 m amsl), a rural site in the central IGB, have been employed to assess the performance of MODIS AOD products against AERONET AOD and to examine their annual and inter-annual variability. For both MODIS Terra/Aqua sensors, the linear regression data statistics reveals that the values of slopes for MODIS Terra-EOS sensor lie in the range 1.04?±?0.03 [DB (QA?=?2,3)] to 1.11?±?0.02 [DT (QA?=?(2,3)] which are slightly higher than 1. Also, similar observation is noticed for MODIS Aqua-EOS sensor for which slopes of linear regression fit span over 0.99?±?0.03 [DB (QA?=?2,3)] – 1.16?±?0.03 [DT (QA?=?3)]. The intercept, however, approach zero values for both MODIS Terra/AQUA–EOS sensor at DT (QA?=?3), DT (QA?=?2,3), DB (QA?=?2,3) and DTB combined retrieval algorithms. The evaluation/performance analysis, therefore, exhibits the observed near-perfect match of MODIS Terra/Aqua-EOS sensors derived AOD550nmfrom all algorithms with AERONET measured AOD550 nmas a result of magnitudes of the slope and intercept of the linear regression fit to the scatter diagrams of MODIS AOD550nm against AERONET AOD550 nm. Results, thus indicate that at Gandhi College, the DT, and DTB combined retrieval algorithms satisfactorily estimate AOD products which can then be used to build aerosol climatology over Gandhi College. The MODIS and AERONET derived AOD550 nmvalues over the Gandhi College indicate a distinct annual pattern with maximum AOD550 nmduring the winter season and minimum AOD550 nmduring monsoon season and winter-summer transition period. Analysis revealed that the aerosol loading starts building up over the study region from March to June of the pre-monsoon season mainly due to the high convective activity and long-range mineral dust transport from western arid regions. An increase in AOD values during the post-monsoon and winter season is primarily due to the influx of aerosols from biomass burning processes and stable atmospheric conditions, the MODIS Terra retrieved AOD550 nmusing DT and combined DTB algorithm showed higher values in the month of July of monsoon season as compared to MODIS Aqua retrieved AOD550 nm. The inter-annual AOD trend analysis reveals that for MODIS Terra satellite there exits an increasing AOD trend during post-monsoon and winter seasons for DT (0.0233 year–1), DB (0.0239 year–1) and DTB (0.0246 year–1), retrieval algorithms. For MODIS Aqua satellite also, there exists an increasing AOD550 nmtrend with differing but higher AOD year–1trend value. On the contrary, for monsoon and pre-monsoon seasons, for MODIS Terra and Aqua satellite, the AOD trends are found to be statistically insignificant.

In the past few years, there has been a proliferation in commercial wireless services such as mobile, Wi-Fi, TV, etc. This has raised a demand for radio spectrum. As per the reports of spectrum occupancy and spectrum policy task force, most of the allocated spectrums are underutilized. Cognitive radio is an emerging technology, which can improve the spectrum utilization efficiency. Reliable spectrum sensing decision-making is a strenuous task in multi-user cognitive radio network (CRN). For enhancing spectrum utilization of such a network and obtaining a faster collaborative decision from honest secondary users, this paper proposes a reliable intra-coalition and inter-coalition decision-making technique (DMT). In this technique, the investigation of Pareto optimal coalitions is performed. Spectrum/channels have been allocated based on Pareto optimality of coalitions. Further, the performance of multi-user CRN has been evaluated using the proposed and traditional DMTs (i.e.OR/AND/maximum voting/half voting rules). It has been noticed that the proposed DMT outperforms DMTs. The performance parameters such as fusion decision processing time and the end-to-end communication delay to obtain a reliable collaborative decision have been reduced by approximately 50% using the proposed DMT compared to the traditional DMTs.

BaSO4:Eu is a highly sensitive high Z thermoluminescence (TL) phosphor. The conventional synthesis of BaSO4:Eu yields very good TL sensitivity but weak optically stimulated luminescence (OSL) sensitivity. Earlier, we have reported novel synthesis method for the preparation of europium-doped BaSO4having good OSL sensitivity. This work reports OSL in nano- and microcrystalline phases of BaSO4:Eu. The study showed that the BaSO4:Eu sample in submicron size shows high TL as well as OSL sensitivity and its OSL sensitivity is 17% compared to the commercial alumina-doped carbon (Al2O3:C, Landauer Inc.). The TL peak at 200 °C gets depleted by 77% after the BSL readout. The dose response of the sample is linear in the 10 mGy–1 Gy dose range with MDD of ~ 10 μGy. For first ten days, practically no fading is observed and the phosphor shows excellent reusable property. High sensitivity, good reusability and low fading of the phosphor will make it suitable in radiation dosimetry applications, particularly for X-ray dosimetry using OSL technique.

Byline: Gupta, A. Patil, R. C. Das, A. K. Yadav, M. The vacuum distillation (VD) unit in the petroleum refinery separates the heavier fraction of crude oil from the atmospheric [...]

The esteemed Alphonso mango, cherished in India for its taste, saffron color, texture, and extended shelf life, holds global commercial appeal. Unfortunately, the prevalent spongy tissue disorder in Alphonso mangoes results in a soft and corky texture, with up to 30% of mangoes within a single batch affected. This issue leads to outright rejection during export due to delayed disorder identification. The current assessment method involves destructive sampling, causing substantial fruit loss, and lacks assurance for overall batch quality. In light of the mentioned challenges, this current study focuses on utilizing visible-near infrared (Vis-NIR) spectroscopy as a non-invasive method to assess the internal quality of mangoes. It also enables innovative classification models for automated binary categorization (healthy vs spongy tissue-affected). Through preprocessing and principal component analysis of spectral reflectance data, wavelength ranges of 670–750 nm, 900–970 nm, and 1100–1170 nm were identified for distinguishing healthy and damaged mangoes. Soft independent modelling of class analogy (SIMCA) modelling is a novel approach that can be used to classify mango into healthy and spongy tissue-affected categories for better postharvest management. The accuracy of SIMCA models for classifying mangoes into healthy and spongy tissue-affected classes was highest in the wavelength regions of 670–750 nm and 900–970 nm, being 94.4% and 96.7%, respectively. The spectral reflectance between wavelength region 650–970 nm gave significant and visible differentiation between all stages of spongy tissue, that is, mild, medium, and severe. Furthermore, the application of Vis-NIR spectroscopy alongside SIMCA modelling offers a viable avenue for examining internal abnormalities resulting from diseases or injuries in fruits, broadening its utility for diverse inspection needs.

Garlic and its preparations have been widely recognized as agents for prevention and treatment of cardiovascular and other metabolic diseases such as, atherosclerosis, hyperlipidemia, thrombosis, hypertension and diabetes. It is also effective against bacterial as well as fungal infections. Garlic oil obtained by two methods steam distilation and cold maceration. Garlic has different active constituents among which ajoene shows antibacterial and antifungal activity. Ajoene is highly unstable it remains stable only in oil macerate form. It is a great challenge for scientists all over the world to make a proper use of garlic and enjoy its maximum beneficial effect as it is the cheapest way to prevent bacterial as well as fungal infection so, an attempt to form topical gel from garlic oil macerate for its antibacterial as well as antifungal activity and evaluation. Keywords: Garlic oil macerate | steam distillation | cold maceration | Ajoene | Evaluation, Introduction Garlic is used for different purposes such as a palliative for the heat of the sun in field labor, preventing heart disease (including atherosclerosis, high cholesterol, and high blood [...]

Byline: N. Shashikiran, SV. Reddy, R. Patil, G. Yavagal Although temporo-mandibular joint (TMJ) ankylosis is one of the most common pathologies afflicting the facial skeleton, it is also the most [...]

Present study was undertaken to assess the vast changes in the behavior of the course of the Ganga river by the identification of recent changes in planform and dynamic fluvial characteristics of the river and quantification of the meandering indices as well as braiding index for the region Mirapur Khadar to Narora, Uttar Pradesh. Narora barrage is located on the banks of river Ganga and its construction was completed in 1966. After its construction, the braiding index was increased from 0.17 to 0.41 from 1975 to 2015. Meandering indices were observed to be increased from 1.26 to 1.36 within a chronological period from 1975 to 2015. This shows that streams are exhibiting braiding as well as meandering pattern. The construction of Bijnor as well as Narora barrages has affected the planform geometry of river Ganga. The study reveals that the natural as well as anthropogenic factors are responsible for the oscillating nature of river Ganga. The study further reveals that Landsat images can be successfully used to identify the meandering indices, braiding index and planform change.

The need of the substitute fuels in compression ignition engines has been the major requisite of the today’s world. Due to progressive diminution in crude oil and their subsequent environmental effects many researchers are working on various alternative fuels like biodiesel, methanol, alcohols, CNG, LPG, biogas. Fulfillment of the stringent emission norms is also a great concern as the fuel suggested should also offer the desired performance and should be economically and environmentally proven. Hence the oil extracted from the waste tyre is the biggest emanating fuel tested for its behavioral analysis when blended with diesel on single cylinder Variable compression ratio diesel engine. Trials are conducted with 100% diesel and then 10%, 25%, 35%, 50%, 60%, 75% and 90% TPO (tyre pyrolysis oil) blends with diesel with varying the load. It is observed that the various performance indicators like BP, IP and BMEP are boosted with rise in the proportion of TPO in the fuel oil for all loads. Increase in the BTE is found highest for moderate load up to 2.6 kg and maximum for TPO 90. Mechanical efficiency found to be maximum at TPO 35 at higher load. Lower specific fuel consumption obtained for TPO10 blend at low load and maximum at TPO 60. From the emission analysis it is found that CO emission tends to reduce up to moderate load, but increases consistently further with the load. HC emission found to be decreased with increase in TPO proportions with minimum for TPO 90 at all loading conditions. CO2emission gradually increased with progressive rise in the load and increases rapidly for higher loads. NOxemission and smoke increased gradually with increase in the TPO proportion. Analyzing the performance of TPO for different proportions with diesel, TPO 90 is the better alternative to enhanced output and efficiency. Whereas for lower fuel consumption and emissions TPO 10 be recommended. Again it is also seen that moderate proportion of TPO (TPO35) gives highest cylinder pressure and reduction in the fragrant sulfur.

Indian gooseberry (Emblica officinalisL.), an important fruit crop, is being grown on commercial scale in different parts of India. There is a great demand for aonla fruits and its products owing to their nutritional, medicinal properties and delicacy. The present investigation aimed at finding out suitable packing material and storage conditions for retention of chemical properties in osmo-air dried aonla segments as in the fresh product/fruits. Different kinds of packages viz. 200 gauge high density polyethylene bag, punnet and polyethylene terephthalate (PET) jar were used to pack freshly prepared product. Packed samples were stored at room temperature under light and dark conditions, and at low temperature for 6 months. Results revealed that samples packed in PET jar and stored at low temperature retained highest ascorbic acid and acidity. Furthermore, there was an increase in reducing sugar, total sugars, and partial reduction in non-reducing sugar content of the product during storage. Samples stored at low temperature showed lower non enzymatic browning values than the samples stored at room temperature. Among different treatments, significantly low non enzymatic browning (0.043 OD at 440 nm) was recorded in product stored in PET jar at low temperature. Same treatment was rated the best during the sensory evaluation, thus it could be concluded that, packing the produce in PET jar and storing them under low temperature is a promising way to improve the storage life of osmo-air dried aonla segments.

A large proportion of villages in India have been connected with water bound macadam (WBM) or bituminous roads. Rural roads usually have a low volume of traffic, consisting mostly of light transport vehicles with less frequency of heavy traffic. Maintenance of these roads is neglected because of the paucity of funds and the created road asset is in deteriorated condition. The non-availability of suitable soil and aggregates has made projects unviable and cost prohibitive. This aggregate scarcity will increase further as a result of environmental conservation and restriction on mining. There is a need to develop alternative pavement designs to construct sustainable and durable rural roads. The stabilization of soil/aggregate is being used worldwide towards optimal usage of scarce resources. The concepts of soil/aggregate stabilization and Cold In Place Recycling technique provide a comprehensive solution for rehabilitation of existing road and greenfield road construction. Cold In Place Recycling process allows usage of locally available marginal materials. The stabilization process can use a wide range of stabilization agents such as soil-aggregate mix, lime, cement, fly ash, foamed bitumen, emulsion, polymers, and other proprietary chemical stabilizers. Two rural roads are identified under Mukhya Mantri Gram Sadak Yojana Research and Development Scheme. Pavements are designed considering cement treated base. These roads are constructed using the Cold In Place Recycling technique. The existing water bound macadam (WBM)/deteriorated bituminous surface is stabilized with cement. Bituminous concrete and Thin White Topping are provided as wearing course. The performance of pavement is evaluated after 2 years of construction. Also, the balance life of the pavement is checked and the results are satisfactory. The stabilized pavements offer superior strength and longevity, even in extreme climatic conditions, and provide better performance. The design charts for Thin White Topping for rural roads are not available, hence the design charts for Thin White Topping of M30/M35/M40 grade concrete on Cement Treated Base of varying thickness and different subgrade CBR are prepared based on IRC 62-2014 for traffic less than 50 CVPD, 51 to 150 CVPD, and less than 450 CVPD. These charts are ready to use and act as a guide to the Field Engineers. The optimum thickness of Thin White Topping can be selected from the chart for known subgrade CBR and Traffic. The effect of variation of CTB thickness on Thin White Topping thickness can be determined from the chart.

AbstractA dominant bioflavonoid-rutin was isolated from the fermentation broth of endophytic Aspergillus flavusobtained from Aegle marmelos.A simple, rapid and reliable High-Performance Thin-Layer Chromatographic (HPTLC) method was developed for the analysis of rutin. HPTLC was carried out for qualitative determination of flavonoids in the fermentation broth using silica gel 60 F25420×20cm thickly plated preparative chromatography plates as a stationary phase and ethyl acetate, glacial acetic acid and formic acid (5:0.5:1, v/v) as mobile phase. The plates were scanned densitometrically between 200 and 700 nm. The fermentation extract of the endophytic Aspergillus flavusproduced metabolite and showed a compact and well resolved blue band with the same Rf(0.32±0.02) to that of authentic rutin. The bioactive metabolite produced by endophytic fungi is generally less than their host plant. However, in this study, the flavonoids were easily detected with HPTLC indicating more production of the metabolite. The present study demonstrates a new method to produce, isolate and analyze flavonoids by fungal fermentation, which could overcome the extensive use of the host plant.

Rapid electrode wear due to localised random alloying between copper and aluminium at high temperature is by far the greatest challenge for the resistance spot welding of aluminium alloys. An effective recourse would be to enhance the overall electrical conductivity along the electrode/sheet interface to reduce the resistive heating of copper electrode and to prohibit direct contact between electrode and sheet during welding. We propose here the application of carbon black paste in fluidic form as a barrier along the electrode/sheet interface both for the enhancement of electrical conductivity and for the prohibition of direct electrode to sheet contact. Carbon black is chemically inert to both copper and aluminium and in fluidic form allows the enhancement of thermal and electrical conductance due to better conformability within a pressurised contact. The present experimental study has shown a significant enhancement in electrode life in the presence of the carbon black based barrier coating along the interface.

ABSTRACTIn this article, we describe a chronic case of rhinofacial mucormycosis caused by Mucor irregularis, formerly known as Rhizomucor variabilisvar. variabilis, a rare mycotic agent in humans. The infection caused progressive destruction of the nasal septum and soft and hard palate, leading to collapse of the nose bridge and an ulcerative gaping hole. The mucoralean mold cultured from a nasal biopsy specimen was determined by multilocus DNA sequence data to be conspecific with M. irregularis.

Indoles represent an important structural class in medicinal chemistry with broad spectrum of biological activities. The synthesis of indoles, therefore, has attracted enormous attention from synthetic chemists. Microwave methods for the preparation of indole analogs have been developed to speed up the synthesis, therefore, microwave assisted organic synthesis (MAOS) in controlled conditions is an invaluable technique for medicinal chemistry. In this review, indole forming classical reactions such as Fischer, Madelung, Bischler-Mohlau, Batcho-Leimgruber, Hemetsberger-Knittel, Graebe-Ullmann, Diels-Alder and Wittig type reactions using microwave radiation has been summarized. In addition, metal mediated cyclizations along with solid phase synthesis of indoles have been discussed.

In this paper, we report a facile biological method for extracellular synthesis of copper oxide nanoparticles (CONPs) using Escherichia coli (E. coli). We report that trichloroacetic acid (TCA) precipitated protein fraction of E. coli has synthesized copper oxide nanoparticles (CONPs), under simple experimental conditions like aerobic environment, neutral pH and room temperature. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results have shown that proteins of molecular weight ranging from 22 KDa, 52 KDa, and 25 KDa are not only involved in reduction of Cu (II) into CONPs, but also play a significant role in stabilization of formed nanoparticles at room temperature. Further, transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction measurements (XRD) and fourier transform infrared (FTIR) analysis have confirmed the synthesis of nanoparticles through microbial route. CONPs formed were of variable size and shapes.

Abstract: Whey containing 4.4% (w/v) lactose was inoculated with Kluyveromyces marxianus MTCC 1389 for carrying out studies related to β-galactosidase production. β-galactosidase activity was found to be maximum after 30 h and further incubation resulted in decline in activity. The maximum cell biomass of 2.54 mg mL−1 was observed after 36 h of incubation. Lactose concentration dropped drastically to 0.04 % from 4.40% after 36 h of incubation. Out of the four methods tested for extraction of enzyme, SDS — Chlorofom method was found to be best followed by Toluene — Acetone, sonication and homogenization with glass beads in that order. It could be concluded through this study that SDS — Chloroform is cheap and simple method for enzyme extraction from Kluyveromyces cells, which resulted in higher enzyme activity as compared to the activity observed using the remaining extraction methods. The study could also establish that whey could effectively be utilized for β-galactosidase production thus alleviating water pollution problems caused due to its disposal into the water streams.

Protein content and gluten strength are the major parameters, which decide the firmness, stickiness and cooking loss of pasta. In the present study, a population of 140 F2:7recombinant inbred lines derived from a durum wheat cross was analyzed for the association of protein and PCR based markers with gluten strength as estimated by sodium dodecyl sulfate-sedimentation (SDSS) volume. The regression analysis showed strong association of Glu-B3a, Glu-B2aand one ω-gliadin band coded by Gli-B3locus with the SDSS volume. The association between gluten strength and Glu-B2/Gli-B3loci is new observation. Glu-B1bwas also found to be associated with gluten strength, while no association of Glu-A3locus was observed. All these markers collectively explained 51.9% to 59.1% variation in SDSS volume at three diverse environments.

Ethylene pressure was used to vary the molecular architecture of amorphous polyethylenes synthesized with a palladium−bisimine catalyst. At low ethylene pressure, densely branched polymers are formed, and their melt rheology indicates no entanglement even though the weight-average molar mass is 370 000. Polymers produced at higher ethylene pressures have only slightly higher molar masses but show entanglement effects in their rheology. NMR suggests similar levels of short-chain branching (92−97 branches per 1000 carbons) in all the samples. A simple model of polymerization, based on the proposed “chain-walking” mechanism for this catalyst, is used to generate structures via computer simulation. While some of the experimental data are consistent with the predicted molecular structures, there are discrepancies in (i) the scaling of radius of gyration with molecular weight and (ii) the variation of terminal relaxation time with ethylene pressure, both of which suggest long-chain branching, which is not predicted by the computer simulation.

Thermoluminescence (TL) in various Cu⁺-doped materials is studied. A good correlation between the presence of copper in the Cu⁺ form and TL sensitivity is observed. Correlation between TL emission spectra and photoluminescence suggests that Cu⁺ acts as the emission center in the TL process. (© 2003 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Within the framework of the polymer reference interaction site model (PRISM) theory, we formulate a simplified method for enforcing conformational self-consistency associated with screening of intrapolymer excluded-volume interactions. It is built on a utilization of the Flory ideality concept, preaveraging of site inequivalency, and the insensitivity of equation-of-state properties of chemically identical polymers to global architecture variation at constant temperature and pressure. The approach allows calculation of the influence of chain branching on average macromolecular stretching under meltlike conditions. Nonideal conformational swelling, intermolecular pair correlation functions, and the cohesive energy as a function of architectural variables have been studied for a variety of star and regular comb models. Predictions for a specific highly globular comb melt are in good agreement with a recent experiment. The relatively weak influence of the nonuniversal local aspect ratio and melt compressibility on polymer stretching is also established. Implications for the χ parameter in isotopic star or comb blends, and the miscibility of mixtures of linear and branched polymers, are briefly discussed.

The purpose of this study was to study the spatial patterns of ambient air quality in Delhi in the absence of extensive datasets needed for space-time modeling. A spatial classification was attempted on the basis of ambient air quality data of nine years 1998 is latest year for which published data were available for three criteria pollutants – nitrogen dioxide, sulfur dioxide, and suspended particulate matter. Monitoring stations take 24-hour samples twice a week. Published monthly average concentration data were used in this study. A hierarchical agglomerative algorithm using the average linkage between groups method and the Euclidean distance metric was used. Cluster analysis indicated that till 1998, by and large, two distinct classes existed. The results of cluster analysis prompted an investigation of systematic biases in the monitored data. No statistically significant differences in the mean concentration of all pollutants were observed between stations belonging to different land-use types residential and industrial. This fact would be useful, if and when the authorities consider modifying the network or expanding it in Delhi. The results also support the recommendation that Delhi have a uniform standard across all areas. This study has provided a methodology for Indian researchers and practitioners to do an exploratory study of spatial patterns of air pollution and data quality issues in Indian cities using the National Ambient Air Quality Monitoring System data.

An efficient use of triphosgene for the preparation of various azidoformates from alcohols and sodium azide is described. The method is applied to various chiral alcohols including glucose diacetonide to get the corresponding azidoformates. One of these azidoformates has been successfully utilized for the synthesis of N-carbobenzyloxy-β-lactams.

A simple method of depositing a uniform layer of polyaniline (PANI) on the surface of acrylonitrile butadiene styrene (ABS) is described. The method consists of two steps, in which the first step is composed of soaking of ABS in aniline solution, and the second step consists of polymerization of aniline absorbed inside the ABS matrix by an oxidant. The ABS surface is seen to be completely masked by the PANI layer when it is coated from solution containing 10 or 15% of aniline. The surface resistance of the ABS plate, which is coated from a solution containing 15% aniline, shows resistance of 30 kΩ and rises up to 400 kΩ as concentration of aniline in the solution is decreased to 5%. From scanning electron micrographs, a granular growth of PANI is noticed on the ABS surface. Thermal gravimetry–mass spectroscopy data reveal that coating the ABS plate with PANI does not weaken an ABS matrix. The adherence of PANI on the ABS surface is explained on the basis of interaction between the aniline and cyano group from the acrylonitrile moiety of ABS. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1904–1910, 2002

Conducting polymer coatings on ABS were prepared by dipping them into m-cresol solutions containing polyaniline (PANI), poly(o-toluidine) (POT), and poly(o-anisidine) (PoAN) protonated with dioctyl hydrogen phosphate (DiOHP) in the presence and absence of polystyrene (PS). The surface resistivity of ABS plates coated with DiOHP-doped PANI in the presence and absence of PS were 5.3 × 10⁷ and 3.0 × 10⁵ Ω, respectively. The ABS plates coated with DiOHP-doped PoAN and -doped POT showed higher resistivities (4.2 × 10⁹ and 2.4 × 10⁷ Ω, respectively) than that with DiOHP-doped PANI. Although the conductivity of the coated ABS with DiOHP-doped PANI was less in the presence of PS, the permanency and uniformity of the coating, which are very important for practical use, were much improved. Coatings and the coated ABS were characterized by X-ray diffraction, TG/MS, SEM, and reduced viscosity measurements. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2661–2669, 2001

Various protonated poly(o-anisidine) (PoAN)/poly(vinyl alcohol) (PVA) composites were prepared with different types of acids: sulfuric (SA), p-toluene sulfonic (TSA), camphor sulfonic (CSA), and p-dodecylbenzene sulfonic (DBSA). In the visible spectrum of each composite in dimethyl sulfoxide, three absorption peaks were observed at 440, 620, and 860 nm. The peaks at 440 and 860 nm, which were enhanced with the increasing content of acid-doped PoAN in the PVA matrix, were attributed to the radical cation and localized polaron generated in the conducting polymer. However, the peak at 620 nm was ascribed to the emeraldine base (EB) form of PoAN; that is, a portion of the acid was detached from the conducting polymer to form EB-PoAN and free acid. The linear dependence of the logarithmic electrical conductivity on the variation of humidity, which was observed for all the composites, was caused by the salt–base transition of the conducting polymer, that is, by the movement of free acid between the active sites of the conducting polymer and the strongly bound water existing in PVA, which in turn depended directly on the environmental humidity. The response time of the composites to humidity was shortened with a decrease in the size of the dopant anions: DBSA > CSA > TSA > SA. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 4343–4352, 2000

Gelatin films that had been chemically modified (crosslinked with formaldehyde, glyoxal, glutaraldehyde, hexamethylene diisocyanate, butadiene diepoxide, or diepoxyoctane) were tested for their biodegradability by soil burial testing in a laboratory environment under temperature and humidity control. The relationship between weight loss and time of biodegradation showed a linear behavior for all the samples, but the rate of biodegradation showed a dependence on the type of crosslinking agent. The most stable films were those crosslinked with aldehydes, and these biodegraded by the 10th day. The samples crosslinked with hexamethylene diisocyanate and diepoxides completely biodegraded by the fourth and sixth days, respectively. It was shown that the rate of biodegradation depended on the density of crosslinking, which was calculated by a modified Flory–Rehner equation. The biodegraded samples showed considerable changes in the fingerprint region of FTIR spectra, and, thus, these spectra could be used for evaluation of the soil burial biodegradation of chemically modified gelatin samples. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1341–1347, 2000

The stretching-induced alpha−beta polymorphic transition in the crystalline regions of poly(butylene terephthalate) (PBT) is studied by small-angle X-ray scattering (SAXS), instead of by the wide-angle X-ray scattering (WAXS) usually used for this purpose. An expression for the increase of the long spacing upon the transition is derived from a simple model of oriented PBT as a set of microfibrils, each consisting of alternating crystalline and amorphous regions. This increase is calculated on the basis of the c unit cell parameter of both alpha and beta phases and the degree of crystallinity as obtained from differential scanning calorimetry. There is a fairly good agreement between this value and the experimentally measured one. The affine deformation model holds for both the alpha and beta phases in the whole interval of the strain, from zero up to the strain at break. Without external stress the microfibrils are in the fully relaxed state, as concluded from the values of the corresponding long spacing (from SAXS) comprising exclusively the alpha modification (from WAXS). Both the polymorphic transition and the change in the long spacing with strain are completely reversible in the deformation range investigated.