A study of external mass transfer effect on biodegradation of phenol using low‐density polyethylene immobilized Bacillus flexus GS1 IIT (BHU) in a packed bed bioreactor

The impact of external mass transport on the biodegradation rate of phenol in a packed bed bioreactor (PBBR) was studied. A potential bacterial species, Bacillus flexus GS1 IIT (BHU), was isolated from the petroleum‐contaminated soil. Low‐density polyethylene (LDPE) immobilized with the B. flexus GS1 IIT (BHU) was used as packing material in the PBBR. The PBBR was operated by varying the inlet feed flow rate from 4 to 10 mL/min, and the corresponding degradation rate coefficients were found to be in the range of 0.119–0.157 L/g h. In addition, the highest removal rate of phenol was obtained to be 1.305 mg/g h at an inlet feed rate of 10 mL/min. The external mass transfer was studied using the model . A new empirical correlation for the biodegradation of phenol in the PBBR was developed after the evaluation at various values of K and n.     

Band-gap tuning of pendant polymers for organic light-emitting devices and photovoltaic applications

The preparation of a series of novel polymers comprising pendant electro-active “push–pull” chromophores and their performance in solution-processed organic electronic devices is described. The design of the electro-active pendant chromophores was based on the well-known motif of cyano-substituted poly(p-phenylenevinylene). Optical band-gap engineering within this series of polymers was achieved by varying the conjugation length and the electron donor/acceptor functionalities of the pendant chromophores. The introduction of a cyanoimine group into the electro-active pendant module resulted in a marked narrowing of the optical band-gap compared with the other electro-active pendant chromophores investigated in this work. Bulk heterojunction solar cell devices comprising these polymers were prepared by solution processing blends of each polymer with [6,6]-phenyl-C₆₁-butyric acid methyl ester, and their performance was evaluated by measuring power conversion efficiencies. The best-performing solar cell in this series exhibited a power conversion efficiency of 0.29% and a maximum incident photon-to-current conversion efficiency of 22% and was produced using the polymer in which the electro-active chromophore comprised the cyanoimine group.     

Stress, coping and psychological illness: A cross-cultural study.

This cross-cultural research study aimed to explore the relationship of stress and coping with psychological illness or symptoms among university students in Canada and India. The predictor variables were stress (hassles and life experience), 8 ways of coping (Folkman & Lazarus, 1988), and selected personal-social variables, namely, locus of control, self-esteem, and social support. The criterion variables were 9 psychological symptoms of the Brief Symptom Inventory (BSI; Derogatis & Spencer, 1982). The results revealed that the Indian students reported more psychological symptoms compared to the Canadian students. Stepwise multiple-regression analyses also revealed considerable differences between the 2 samples with respect to the contribution of predictor variables in accounting for variance in the BSI scales. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pressure synthesis of dibenzylamine from benzylamine and benzyl alcohol

The synthesis of dibenzylamine from benzylamine and benzyl alcohol in the presence of a phosphoric acid catalyst has been carried out under pressure. Very high pressure has no beneficial effect on the synthesis of dibenzylamine. Under optimum conditions (473K, 3.10×10⁶Nm^?2; residence period 2h; benzylamine to benzyl alcohol mol. ratio, 1:2 and benzylamine to catalyst mol. ratio, 1:0.2174), the conversion of benzylamine to dibenzylamine was 88.50%.     

Kinetics and mechanism of adsorption of triton x-100 on a reservoir sand

Adsorption of Triton X-100 on a reservoir sand (characterised by chemical analysis and i.r. spectra to be silica) has been studied under field conditions. The adsorption behaviour is best characterised by Freundlich and Temkin adsorption models. The kinetics of adsorption is found to be very much dependent on temperature and the rate of adsorption shows an anti-Arrhenius temperature dependence. The adsorption is proposed to proceed through Si—CH₃ bond formation. Addition of common inorganic salts is found to cause maxima and minima in the adsorption isotherm and to change the shape of the isotherm.     

Monitoring the Channel Formation in Organic Field‐Effect Transistors via Photoinduced Charge Transfer

Conducting channel formation in organic field‐effect transistors (OFETs) is considered to happen in the organic semiconductor layer very close to the interface with the gate dielectric. In the gradual channel approximation, the local density of accumulated charge carriers varies as a result of applied gate bias, with the majority of the charge carriers being localized in the first few semiconductor monolayers close to the dielectric interface. In this report, a new concept is employed which enables the accumulation of charge carriers in the channel by photoinduced charge transfer. An OFET employing C₆₀ as a semiconductor and divinyltetramethyldisiloxane‐bis(benzocyclobutene) as the gate dielectric is modified by a very thin noncontinuous layer of zinc‐phthalocyanine (ZnPc) at the semiconductor/dielectric interface. With this device geometry, it is possible to excite the phthalocyanine selectively and photogenerate charges directly at the semiconductor/dielectric interface via photoinduced electron transfer from ZnPc onto C₆₀. Thus the formation of a gate induced and a photoinduced channel in the same device can be correlated.     

Comparative study of allelopathy as exhibited byProsopis Juliflora swartz andProsopis cineraria (L) druce

The allelopathic effects ofProsopis juliflora were studied both in the laboratory and in nature and compared with that ofProsopis cineraria to understand the chemical nature of allelochemics. Both species occupy the same habitats butP. cineraria does not appear to have any toxic effect on other plants under its canopy.P. juliflora is highly allelopathic and does not allow the growth of any other species. Leaf extracts and leaf leachates ofP. juliflora were inhibitory. Decaying leaves were also inhibitory at early stages of decomposition. Live roots were not found to be inhibitory in cogermination and interplanting of seeds. Chemical investigation of the extracts showed the allelopathic compounds to be phenolic in nature in both the species. Slow decomposition and heavy accumulation of leaf litter belowP. juliflora may possibly result in accumulation of toxic substances in soil layers, inhibiting growth of other species.     

Anti-melanogenic effect of <Emphasis Type="Italic">Prunus davidiana</Emphasis> extract in melan-a melanocyte through regulation of OCA-2, TRP-1 and tyrosinase

Prunus spp. and locally available plants (used as folkloric medicine) were screened to find a novel and natural anti-melanogenic agent. Based on p-protein promoter reporter assay (PPRA) the candidate plants were screened in the quest for p-protein inhibitor. Expression profiling of key proteins revealed the molecular mechanism of the melanin inhibition as well as TEM analysis revealed melanosome structure. The screened plant extract through PPRA showed significant down regulation of p-protein, which led to melanin inhibition. Another key melanosomal protein like tyrosinase and TRP-1 was also found to be down-regulated. However, TRP-2 was not affected. TEM analysis of treated cells also revealed that the stage IV melanosomes were lowered in number compared to control. The present study shows the plants used in this study possess good anti-melanogenic properties. However, the P. davidiana has the highest anti-melanogenic property among screened plant extracts.     

Effects of ordering on the properties of Ni-Cr alloys

A large number of commercial nickel-based alloys are likely to undergo an ordering transformation based on an Ni₂Cr ordered phase formation at temperatures below 550° C. A shortrange ordered structure develops in the matrix phase at an early stage of ageing. This can transform to long-range ordering depending upon the composition, after prolonged exposure. The Ni/Cr ratio in the majority of these materials is considerably different from the stoichiometric composition of Ni₂Cr and hence they may not form the long-range ordered phase. Ordering, both short and long-range, is known to have the following consequences: (i) dimensional instability due to lattice parameter contraction; (ii) electrical and thermal characteristics variations; (iii) changes in mechanical properties due to pile ups of dislocation dipoles; (iv) the phenomenon of negative creep or material contraction under load.