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181.
塔里木河水质现状综合评价   总被引:5,自引:0,他引:5       下载免费PDF全文
塔里木河水质污染对中、下游地区的生态系统的稳定性及社会的持续发展带来了不利的影响。利用阿克苏河的龙口、西大桥断面以及塔里木河干流上游的阿拉尔、十四团断面2001-2005年实测数据,在统计软件STATISTICA的支持下,利用主成分分析方法和水质指数法进行了塔里木河水质评价研究。结果表明,龙口和西大桥断面的水质属于一级(清洁)水,而阿拉尔和十四团断面的水质属于4级(中等污染)及5级(重污染)水。塔里木河的主要污染物为氯化物、总硬度、矿化度、硫酸盐、亚硝酸盐等。  相似文献   
182.
Sagdic  Osman  Polat  Busra  Yetim  Hasan 《Erwerbs-Obstbau》2022,64(2):299-305

In this study some bioactive properties of extracts of wild pear (Pyrus elaegnifolia), hawthorn (Crataegus spp.), oriental hackberry (Celtis tournefortii), oleaster (Elaeagnus angustifolia), Japanese crabapple (Malus floribunda), rosehip (Rosa canina), pedunculate oak (Quercus robur), service tree (Sorbus domestica) and firethorn (Pyracantha coccinea) wildly growing in Turkey were investigated. The fruit extracts were analysed in terms of total phenolic content (TPC), antioxidant activities (DPPH and phosphomolybdenum methods) and antimicrobial activity. In the results, TPC, IC50 value of DPPH and IC50 value of phosphomolybdenum for pedunculate oak were 454.35?mg GAE/g d.w., 340.52?mg AAE/g d.w. and 96.52%, respectively. Service tree and firethorn exhibited the lowest TPC (4.11?mg GAE/g d.w.) and IC50 value of DPPH (53.32?mg AAE/g d.w.), respectively. Moreover, antimicrobial activity of oleaster was 2.46%. The hackberry fruit extract had no inhibitory effect against the tested microorganisms whereas pedunculate oak extract (with 10%) had the highest inhibitory effect against Aeromonas hydrophila. Additionally, all the fruit extracts had no antimicrobial activity against the Saccharomyces cerevisiae. In conclusion, wild edible fruit extracts can be used as bioactive material due to their antioxidant and antimicrobial activity in food industry and human nutrition.

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183.

In this research, proximate composition, mineral composition and color characteristics of hazelnuts grown by conventional and organic methods in East, Central and West Black Sea Regions (Turkey) that are the center of world hazelnut production were investigated. Commercially important ‘Çak?ldak’, ‘Fo?a’, ‘Mincane’, ‘Palaz’, ‘Sivri’ and ‘Tombul’ varieties were selected as research material. As a result of the analysis, it was determined that organic hazelnuts contain lower moisture and higher ash, no difference was found in protein, fat and carbohydrate amounts. In terms of all micro elements (boron, copper, iron, manganese, zinc) organic hazelnuts were found to be richer and potassium from macro elements were found to be higher in conventionally grown hazelnuts. Color properties were generally not affected by the production method and no loss of color was observed in organic hazelnuts. The high ash and micro element content of organic hazelnuts compared to the conventional hazelnuts would be a good alternative for the elimination of micro element deficiency, which is frequently seen in human nutrition.

  相似文献   
184.
Composite materials have a wide range of applications in structural components because of their high strength-to-weight and stiffness-to-weight ratios. However, the most crucial and common life-restricting crack growth mode in laminated composites i.e. delamination is of great concern. Air jet texturing was selected to provide a small amount of bulk to the glass yarn. The purpose was to provide more surface contact between the fibres and resin and also to increase the adhesion between the neighbouring layers. These were expected to enhance the resistance to delamination in the woven glass composites. The development and characterisation of core-and-effect textured glass yarns was presented in the previous paper. This paper describes the comparison of the mechanical properties of composites produced from air-textured glass yarns and the composites made from locally manufactured carbon fabrics. The tensile, flexure and inter-laminar shear strength (ILSS) were compared and it was observed that although glass fibres are inferior to carbon fibres in terms of mechanical properties however, the flexure strength and ILSS of glass based composites increases after texturing and were found closer to the properties of carbon based composites.  相似文献   
185.
186.
The cytotoxicity and antibacterial activity of petroleum ether, chloroform and methanol extracts of Wedelia calendulacea were assayed by brine shrimp lethality bioassay and standardized disk diffusion method against 19 bacterial strains. Three diterpenes isolated from the plant were also evaluated for in vitro antibacterial activities. The LC50 for the crude extracts against the brine shrimp nauplii were found to be 4.59 microg/ml, 7.99 microg/ml and 14.88 microg/ml, respectively, whereas the positive control, vincristine sulfate showed an LC50 of 0.58 microg/ml. Among the crude extracts and pure compounds tested, (-)-kaur-16-en-19-oic acid isolated from the chloroform extract showed the highest inhibitory activity against most of the bacterial strains with mean zone of inhibition of 10-21 mm at 200 microg/disc.  相似文献   
187.
Constituents and cytotoxicity of Zanthoxylum rhesta stem bark   总被引:2,自引:0,他引:2  
Ahsan M  Zaman TA  Hasan CM  Ito C  Islam SK 《Fitoterapia》2000,71(6):697-700
3,5-Dimethoxy-4-geranyloxycinnamyl alcohol (1), 8-methoxy-N-methylflindersine (2), xanthyletin and sesamin have been isolated from petroleum ether extract of the stem bark of Zanthoxylum rhesta. The petroleum ether extract and 8-methoxy-N-methylflindersine showed cytotoxicity on brine shrimp nauplii.  相似文献   
188.
In the present study the antigenotoxic effect of apigenin was studied against a genotoxic dose of ethinylestradiol using the damage parameters of chromosomal aberrations (CAs), sister chromatid exchanges (SCEs) and cell cycle kinetics (CCK). Human peripheral blood lymphocytes were cultured and treated with 10 μM of ethinylestradiol along with doses of 5, 10, 15 and 20 μM of apigenin. A clear decrease in the genotoxic damage induced by ethinylestradiol was observed with increasing doses of apigenin, suggesting a protective role for apigenin during ethinylestradiol therapy.  相似文献   
189.
All pestiviruses are important veterinary pathogens causing economic losses in cattle, sheep, and pigs. In this study, blood samples randomly collected from 465 sheep were analysed for the presence of antibodies to pestiviruses (bovine viral diarrhea virus, border disease virus) using an enzyme-linked immunosorbent assay in the province of Van and their towns. The seroprevalance were estimated as 75.9% and 60.0–82.5% in the sampled animals and sampled towns, respectively. The results revealed that pestiviruses are important abort pathogens in the province of Van and their towns.  相似文献   
190.
Coccidiosis is a disease of almost universal importance in Poultry production. The subclinical form of coccidiosis has most significant economic impact due to impaired growth rate and feed conversion. Some factors such as: age, size of flock, season, etc., may effect on severity of this disease. In this study, the relationships between some major risk factors and prevalence of subclinical coccidiosis were investigated. This study was done in 120 broiler farms in five different cities of Mazandaran province, north of Iran. Five chicks (3–8 weeks of ages) were taken randomly from every 120 farms and post-mortem and parasitological examinations were performed. Five Eimeria spp. were recognized: Eimeria tenella, Eimeria maxima, Eimeria acervulina, Eimeria brunetti, and Eimeria necatrix. The prevalence rate of subclinical coccidiosis among them is 75% (90 farms out of 120). E. acervulina was the most prevalent species (65.5%) followed by E. maxima (17.7%), E. tenella (15.5%), E. brunetti (10%), and E. necatrix (5.5%). According to what the results approve, the occurrence of subclinical coccidiosis is significantly related to the age and size of flock, whereas the other factors such as the season of year, industrial strains, chicken’s keeping system, and anticoccidial drugs do not affect this phenomenon remarkably.  相似文献   
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