The interactions between nanoparticles and rough surfaces are of great scientific and engineering importance and have numerous applications in surface science and biotechnology. Surface geometry and roughness play crucial roles in observed particle adhesion forces. We previously developed a model and simulation approach to describe adhesion between microscale bodies. This work provides detailed descriptions of the modeling framework, with associated experimental validation, applied to nanoscale systems. The physical systems of interest include nanoscale silicon nitride adhering to different surfaces in both dry and aqueous environments. To perform the modeling work, precise descriptions of the geometry of the particle and the roughness of the particle and substrate were generated. By superimposing the roughness and geometry models for the particle and the substrate, it was possible to precisely describe the spatial configurations of the adhering surfaces. The interacting surfaces were then discretized, and the adhesion force between the two surfaces was calculated by using Hamaker's additive approach, based on van der Waals interactions. In the experimental work, an atomic force microscope (AFM) was used to measure the adhesion force (pull-off force) between nanoscale silicon nitride cantilever tips and a range of substrates in different environments. The measured and predicted force distributions were compared, and good agreement was observed between theory and experiment.

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Root galls of rice caused by Meloidogyne graminicola were examined for natural colonization by nematophagous fungi from four fields with different nematode infestations. Old galls from severely infested fields had a higher frequency of Monacrosporium eudermatum and Stylopaga hadra than young galls. The frequency of Arthrobotrys oligospora, Arthrobotrys dactyloides, Dactylaria brochopaga and Monacrosporium gephyropagum was lower. A greater proportion (%) of root galls were colonized by nematophagous fungi in those fields in which rice roots had a greater root gall index. This indicated that disease severity supported the colonization of galls by nematophagous fungi. In vitro predacity tests of four fungi showed that A. dactyloides was most effective in capturing and killing J 2 of Mel. graminicola followed by D. brochopaga and Mon. eudermatum. Application of inocula of A. dactyloides and D. brochopaga in soil infested with Mel. graminicola, respectively, reduced the number of root galls by 86% and of females by 94%, and eggs and juveniles by 94%. The application of these fungi to soil increased plant growth: shoot length by 42.7% and 39.8%, root length by 45.5% and 48.9%, fresh weight of shoot by 59.9% and 56.7% and fresh weight of root by 20.3% and 25.1%, respectively, compared to these parameters for plants grown in nematode-infested soil.

Onion (Allium cepa L.) and garlic (Allium sativum L.) are the most important commercial crops grown all over the world and consumed in various forms. In India, onion and garlic have been under cultivation for the last 5000 years. It is generally used as vegetables, spices or as medicines. India ranks second to China in area and production in both onion and garlic, but ranks 102 nd for onion and 74 th for garlic in terms of productivity. These crops are generally grown throughout the country especially in the states of Maharashtra,

The threat of dye contamination has achieved an unsurpassed abnormal state lately due to their massive consumption in several enterprises including textile, leather, cosmetic, plastic, and paper industries. This review focuses on the integrations of various advanced oxidation processes (AOPs), such as Fenton, photocatalysis, and ozonation, with biodegradation for the treatment of textile azo dyes. Such integrations have been explored lately by researchers to bring down the processing cost and improve the degree of mineralization of the treated dyeing wastewater. The review refers to the basic mechanisms, the influence of various process parameters, outcomes of recent works, and future research directions. All the three AOPs, independently, demonstrated substantial color reduction of 54–100%. The ozonation process, stand-alone, showed the most efficient decolorization (of 88–100%) consistently in all reviewed research works. In contrast, all three AOPs independently offered varied and inadequate COD reduction in the range of 16–80%. The AOPs, after getting integrated with biodegradation, yielded an additional reduction (of 11–70%) in the COD-levels and (of 16–80%) in the TOC-levels. Further, the integration of AOPs with biodegradation has potential to significantly reduce the treatment costs. The review suggests further research efforts in the direction of sequencing chemical and biological routes such that their synergistic utilization yield complete detoxification of the textile azo dyes economically at large-scale.

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