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101.
The photodegradation of the carboxamide acaricide hexythiazox in three different solvent systems (aqueous methanolic, aqueous isopropanolic, and aqueous acetonitrilic solutions) in the presence of H(2)O(2), KNO(3), and TiO(2) under ultraviolet (UV) light (λ(max) ≥ 250 nm) and sunlight (λ(max) ≥290 nm) has been assessed in this work. The kinetics of photodecomposition of hexythiazox and the identification of photoproducts were carried out using liquid chromatography-mass spectrometry. The rate of photodecomposition of hexythiazox in different solvents followed first-order kinetics in both UV radiation and natural sunlight, and the degradation rates were faster under UV light than under sunlight. Hexythiazox was found to be more efficiently photodegraded in the presence of TiO(2) than in the presence of H(2)O(2) and KNO(3). Two major photoproducts were separated in pure form using column chromatography and identified according to IR, (1)H NMR, and mass spectral information as cyclohexylamine and 5-(4-chlorophenyl)-4-methylthiazolidin-2-one. Another nine photoproducts were identified according to LC-MS/MS spectral information. The plausible photodegradation pathways of hexythiazox were proposed according to the structures of the photoproducts.  相似文献   
102.
A study was conducted to compare the nutrient utilization, growth, and rumen enzyme profile of mithun (Bos frontalis) and Tho-tho cattle (Bos indicus) reared in the same feeding and managemental conditions. For the purpose, male mithun (n = 8) and male Tho-tho cattle (n = 8) of 1.5 years age, selected from the farm of National Research Centre on Mithun, Nagaland, India, were fed on mixed-tree-leaves-based ration as per the requirement of NRC (2001) for cattle for 12 months. Average daily gain (ADG), average dry matter intake (DMI), and feed conversion ratio (FCR) for all animals were recorded. A metabolic trial was conducted at 6 months of the experiment to assess the digestibility coefficient of different nutrients and nutritive value of ration. At 12 months of the experiment, rumen liquor was collected from all animals and analyzed for rumen enzyme profiles, viz., carboxymethylcellulase, xylanase, α-amylase, β-glucosidase, α-glucosidase, urease, and protease. It was found that ADG (507.8 g vs 392.8 g), DM intake (6.59 vs 5.85 kg/day) and DMI/W0.75 (98.75 g vs 91.00 g/day), crude protein intake (780 vs 700 g/day), and total digestible nutrient intake (3.65 vs 3.32 kg/day) were higher (p < 0.05) in mithun than cattle. The nitrogen balance was higher and FCR was better (p < 0.05) in mithun compared with cattle. The digestibility coefficient of different nutrients was similar (p > 0.05) between the species. The microbial enzyme profiles of mithun and cattle were not different (p > 0.05). The better growth performance of mithun than cattle as found in the present study clearly indicates that the mithun has higher genetic potential for growth than Tho-tho cattle of north-eastern hilly region of India.  相似文献   
103.
104.
Abstract

Rice is mostly transplanted under puddled low land soil conditions in India, where Zinc (Zn) deficiency is a common problem. The objective of this study was to find out the efficacy of split application of Zn on growth and yield of rice in an inceptisol. The split application of Zn as ZnSO4 · 7H2O performed better than its single basal application, while the split application of Zn-EDTA did not show any significant difference on yield and yield components of rice over its single basal application. Zn-EDTA was found to be better for growth and yield of rice among the two sources of Zn. The soil application of Zn at 1.0 kg ha?1 as Zn-EDTA (T7) recorded highest grain yield of 5.42 t ha?1, filled grain percentage of 90.2%, 1000-grain weight of 25.41 g and number of panicles m?2 of 452. The Zn content of grain and straw were found to be maximum in the treatment T7 i.e. 38.19 and 18.27 mg kg?1, respectively. Linear regression studies indicated that grain yield of rice is significantly influenced by Zn content of grain, Zn content of straw and DTPA extractable Zn content of soil at the level of 95.96, 96.74 and 95.57%, respectively.  相似文献   
105.
A field experiment was conducted at Rani Chandramma Agricultural University (Arabhavi, Belgaum), Karnataka, India, in basic soil to study the nutrient availability in soil, yield and yield attributes of the medicinal plant stevia (Stevia rebaudiana). The results showed that the availability of nutrients such as nitrogen (N), phosphorus (P) and potassium (K) in the soil increased up to the fifth month; and thereafter, decreased by the same amount with the progress of the plant growth up to the sixth month, irrespective of treatments. Results also showed that the fresh and dry biomass yields significantly increased up to the sixth month with different treatments, but the yield attributes like plant height and the number of branches were observed to be varied with various treatments, being highest in the combined application of biofertilizers over that of their corresponding sole applications.  相似文献   
106.
The nitrogen (N) fertilizer-use efficiency (20–50%) is low in rice fields in India. The neem-oil coated urea can increase N-use efficiency in lowland rice, but the desirable thickness of neem-oil coating onto urea is not known yet. Therefore, field experiments were conducted during kharif (rainy) season years 2004 and 2005 at the Research Farm of Indian Agricultural Research Institute, New Delhi to know the suitable thickness of neem-oil coating on prilled urea (PU) for increased N-use efficiency and yield. The treatments comprised of twelve combinations of four N sources (PU coated with neem-oil thickness of 0, 500, 1000 and 2000 mg kg?1 PU) and three N levels (50, 100, and 150 kg N ha?1) plus a no-N control. Prilled urea (PU) refers to the common urea available commercially in prills, which is different from urea super granules. Application of urea coated with neem-oil thickness of 1000 mg kg?1 PU resulted in significantly higher growth, yield parameters, grain yield, N uptake, and efficiency of aromatic rice (Oryza sativa L.) over uncoated PU. Nitrogen application at 122 kg ha?1 was optimum for increased yield of rice. Nitrogen-use efficiency decreased significantly and substantially with each successive increase in levels of N from 50 to 150 kg ha?1.  相似文献   
107.
A dynamic model of aerobic composting with solid substrates was developed as a first step to predict the rate of decomposition of cellulosic materials. The model was based on heat and mass transfer principles and reaction kinetics of biological processes. The relations describing the rates of reaction and the degradability potential of the substrates were determined based on laboratory-scale experiments. The model was developed using a graphical software package, Stella II® (which was able to solve feedback loops encountered in actual composting processes.

The model was validated with temperature, oxygen distribution and mass degradation accompanying the composting of bagasse. Experimental setups consisted of 30 gallon drum reactors, continuously aerated. Temperature and oxygen in exhaust gases were monitored on an hourly basis and measurements of moisture content, pH and volatile solids were done on a weekly basis.

The data fit with the model was excellent for mass degraded and temperatures for the first 10 days. From day 10 to 14, the deviations between model predictions (as solved with Stella II®) and actual measurements did not exceed 2.6 percent. The concentrations of oxygen in outlet gases showed fair agreement between predicted and experimental values. Simulating the model with varying airflow rates showed that the maximum mass breakdown rates occurred for airflow rates of 0.12 kg dry air/(kg dry compost.hr) while maintaining the temperatures below 50°C, through a temperature feedback control strategy.  相似文献   
108.
Hemagglutinating activity was identified in the roots and vegetative tissues of Bengal gram using rabbit erythrocytes. The activity in the roots appears to be similar to that of the seeds in respect to their sugar inhibition property. Seed and root extracts were found to have fetuin inhibitory agglutinating activity, whereas cotyledons showed different sugar specificity. However, 7-day cotyledons and roots from 3 and 7-day plants were also found to have galactose and N-acetyl-D-galactosamine inhibitory activity. Protein profile in different tissues during their developmental stages was analyzed by SDS-PAGE. A major band at 66 kDa was common to all tissues at different stages of their development except 3-day cotyledons where 2 major bands at 22 kDa and 74 kDa were observed. Two prominent bands at 74 kDa and 86 kDa were found along with 60 kDa protein in 3-day old roots whereas a major band at 33 kDa was found in 15-day old roots. Total protein content and specific activity of hemagglutinin were measured. Increase in specific activity with lower protein content was observed in cotyledons of 15-day old plant. Specific activity was eight times higher in the roots and four times more in leaf tissues of 7-day old plants in comparison to 15-day old plants. Stems also showed a significant increase of specific activity (p = 0.013) in 7-day old plants without any significant alteration in the protein content.  相似文献   
109.

Background  

We investigated the feeding ecology and habitat use of 32 harbour porpoises by-caught in 4 localities along the Scandinavian coast from the North Sea to the Barents Sea using time-integrative markers: stable isotopes (δ13C, δ15N) and trace elements (Zn, Cu, Fe, Se, total Hg and Cd), in relation to habitat characteristics (bathymetry) and geographic position (latitude).  相似文献   
110.

Background  

Harbour porpoises Phocoena phocoena from the southern North Sea are known to display high levels of Zn and Hg in their tissues linked to their nutritional status (emaciation). The question arises regarding a potential role of metallothioneins (MTs) with regard to these high metal levels. In the present study, metallothionein detection and associated Zn, Cd, Cu and Hg concentrations were investigated in the liver and kidney of 14 harbour porpoises collected along the Belgian coast.  相似文献   
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