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41.
Fossil fuel Is currently the major energy source driving global socio-economy, but its stock Is being heavily depleted due to Increasing anthropogenic activities worldwide. There are also concerns regarding the burning of fossil fuels, which contributes to global climate warming and sir pollution. As such, the development of blodlesel as a non-toxic, blodegredable, and renewable alternative energy source using oil crops such as soybean and rapeseed has quickly emerged in the West countries. However, the production of oil crops In China Is far from sufficient to meet the demands of the country's population of 1.3 billion, and Increasing oil crop production Is Inhibited by a severe shortage of agricultural land, which currently averages 0.2 acre per person and, as such, Is less than half the world average. The current national policy in China regarding land use Is more towards revering cultivated lands in revins and hills to forestry, which presents an ideal opportunity to further develop plantations of walnut (Juglans regis L.) trees, a plant that is tolerant to drought and infertile soils and has a high oil content. Study In this paper shows that one ament of walnut staminate flowers produces about 0.168 g dry pollen, and the dry pollen contained 49.67% oil. Based on this discovery, oil yield obtained from staminate flowers Is estimated to reach 6.95% of that from walnut nuts. Thus walnut staminate flower is suggested to explore as supplementary plant oil source, and has a great opportunity to utilize as a biodlesel feedstock.  相似文献   
42.
Employing a number of physical techniques the transition metal binding site of the bleomycin (BLM) related antibiotic tallysomycin (TLM) has been determined. The new antibiotic was shown to have two metal binding sites. One site is similar to that of bleomycin and involves the pyrimidine-imidazole portion of the molecule. The second binding site, which is thermodynamically less stable than the first site, utilizes the amino group of the L-talose moiety and the amino groups located in the β lysine-spermidine portion of the antibiotic. The presence of two metal binding sites and its implication on the mechanism of action of TLM is also discussed.  相似文献   
43.
Rice is an essential part of the human diet in most parts of the world; On the other hand, the industrialization of societies has led to pollution of the environment, including heavy metal contamination of soil and water, which negatively affects rice production and quality. Therefore, finding ways to increase the yield and quality of this strategic crop seems essential. Several studies have been conducted in recent decades to find effective and inexpensive solutions to reduce the adverse effects of heavy metals in rice fields. Due to the negative effect of cadmium pollution on rice quality and yield, the current study aimed to investigate cadmium absorption and transfer mechanisms in rice (from absorption by roots to loading in grains), and its effects on rice morphology, physiology, and biochemistry (such as biomass, nutrient absorption, antioxidant defenses). Also, rice’s natural mechanisms for detoxifying cadmium were discussed. This study also intended to identify the absorption and transfer pathways of silicon and selenium in rice, their roles in improving rice structures, and their antagonistic effects on reducing cadmium stress (absorption, transport, and toxicity of cadmium).  相似文献   
44.
Activated sludge acclimated to biodegrade phenol was allowed to attach on and in light porous ceramic carriers and to function as a biofilm in a photolytic circulating-bed bioreactor (PCBBR). Phenol degradation in the PCBBR was investigated following three protocols: photolysis with ultraviolet light alone (P), biodegradation alone (B), and the two mechanisms operating simultaneously (P/B). Phenol was degraded at approximately equal rates by B and P/B, each of which was much faster than the rate by P. Furthermore, phenol was mineralized to a significantly greater extent with P/B than with either P or B. SEM showed that the biofilm survived well inside macropores that presumably shaded the microorganisms from UV irradiation, even though the UV light greatly reduced biofilm on outer surface of the carriers in the P/B experiments. Rapid biodegradation of phenol, enhanced mineralization, and survival of bacteria inside macropores demonstrated that being in a biofilm inside the porous carriers protected the bacteria from UV-light toxicity, allowing intimate coupling of photolysis and biodegradation.  相似文献   
45.
The porcine 17β-hydroxysteroid dehydrogenase type 4 is the key enzyme for the inactivation of estradiol. Its localization in peroxisomes was proven by immunogold electron microscopy. Interactions of the 17β-hydroxysteroid dehydrogenase with cytoskeletal proteins might be mandatory for a topical assignment of enzymatic activity to defined subcellular compartments.  相似文献   
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