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121.
The oxidative polycondensation reaction conditions of (E)-3-amino-4-((3-bromophenyl)diazenyl)-1H-pyrazol-5-ol (Schiff base monomer) has been accomplished using NaOCl, and air O2 oxidants in an aqueous alkaline medium. The optical conductivity, dielectric and optical properties of synthesized poly(Schiff base) were examined. The magnitude of the refractive index decreases with increasing of photon energy up to about 2.5 eV, then refractive index of the poly(Schiff base) increases with increasing of photon energy. The E0 and Ed values of the poly(Schiff base) were found to be 5.34 and 9.22 eV, respectively. An indirect energy-gap value of the poly(Schiff base) was found to be 0.94±0.009 eV. A direct energy-gap value of the poly(Schiff base) was found to be 1.38±0.01 eV and 1.96±0.009 eV at first region and second region, respectively. Absorption coefficient K changes from 11.87 to 18.25 cm?1. In addition to fluorescence property of poly(Schiff base) was investigated. Finally, poly(Schiff base) and Schiff base monomer were tested for antibacterial activities against some bacteria.  相似文献   
122.
In this study, multistitched woven nano composites were developed and their in-plane shear properties were characterized. The in-plane shear strength of unstitched structure was low compared to that of the unstitched/nano structures. However, the in-plane shear strength of unstitched structure was high compared to the machine stitched structures because of stitching and stitching yarn-matrix interfacial region. Additionally, the in-plane shear strength of machine stitched/nano composite structure was slightly high compared to the unstitched structure. The multistitched and multistitched/nano structures had limited delamination in their cross-sections. Their delamination regions were confined at a narrow area due to multistitching. This was considered that the developed multistitched/nano composites has better demage tolerance compared to unstitched composites.  相似文献   
123.
The aim of this study was to investigate total antioxidant (TAC), and oxidant capacity (TOC) and nitric oxide (NO) levels in milk of cows with subclinical mastitis. Brown Swiss and Holstein breed cows were screened with California Mastitis Test (CMT) to determine mammary glands with subclinical mastitis. Moreover, somatic cell counts (SCC) were determined electronically in all milk samples. Mammary quarters were classified as healthy (n = 25) or subclinical mastitis (n = 35) based on CMT scores and somatic cell count (SCC: ?200,000/ml or >200,000/ml) in milk. Nitric oxide, TOC and SCC levels were significantly higher (< 0.001, < 0.005 and < 0.001, respectively) in milk from mammary quarters with subclinical mastitis compared to those from healthy mammary quarters. In conclusion, subclinical mastitis results in higher NO concentrations, TOC and SCC, and NO and TOC were positively correlated with SCC. Moreover, alterations in NO levels and TOC in milk could be used as an alternative diagnostic tool to screen for subclinical mastitis.  相似文献   
124.
高校《中国近现代史纲要》课教学过程中,应当注重爱国主义教育的科学性、时代感和针对性。运用科学的历史观和方法论分析评价历史问题、历史人物;注意历史与现实的结合,为爱国主义思想和传统注入新鲜的时代内涵;针对学生的思想实际,解答他们所关注的社会热点、疑点问题。这些对于提高教育的说服力、吸引力和实效性有着重要作用。  相似文献   
125.
n-Hexane, ethyl acetate, ethanolic and aqueous extracts of the bulbs and aerial parts of Sternbergia sicula and Sternbergia lutea were tested for their antimicrobial and antifungal activity.  相似文献   
126.
Rhodococcus equi is an important pathogen in foals; however, its incidence in African indigenous animals is poorly understood. Fecal samples (92 from nine indigenous species) and 43 soil samples were collected from two Zambian National Parks. The presence of R. equi was investigated and 533 isolates were tested for the presence of 15- to 17-kDa antigens (VapA) and a 20-kDa antigen (VapB) by immunoblotting and PCR. R. equi was isolated (10(2)-10(4) colony forming units/g) from 75% of fecal and 74% of soil samples. Neither antigen was detected; however, about 20% of the isolates contained cryptic plasmids of various sizes. There was no evidence of virulent R. equi, but the avirulent form was widespread in the animals and the soil.  相似文献   
127.
Three Aeromonas salmonicida strains were isolated from the livers of 265 rainbow trouts sampled. The antibiotic susceptibility test results showed that A. salmonicida strains were susceptible to streptomycine and ciprofloxacin. However, they were resistant to amoxycilline + clavulanic acid, penicillin, erythromycine, oxytetracycline and cefuroxime sodium.  相似文献   
128.
A total of 135 laying quails (Coturnix coturnix japonica), 9 weeks old, were divided into three dietary treatment groups. Three replicates were assigned to each treatment group consisting of 15 birds per cage. The diet was supplemented with 0, 100 and 200 ppm Yucca schidigera powder and given ad libitum to the quails for a period of 14 weeks. Body weight, egg production, feed consumption and feed efficiency were not different due to dietary treatments among the groups. Increased egg weight was determined in the control group. Yucca powder supplementation decreased serum glucose, cholesterol triglyceride level in laying quails. Serum total protein concentration was not changed by dietary treatments but albumin level was decreased in quails fed 100 ppm yucca powder. Egg yolk cholesterol concentration was not significantly different among the groups but tended to decline (11.5%) as a result of yucca supplementation. Red Blood Cell (RBC) and White Blood Cell (WBC) counts, packed cell volume (PCV), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) were not affected by supplementation of yucca powder. However, haemoglobin (HB) concentration was slightly increased and mean corpuscular haemoglobin concentration (MCHC) was significantly increased by 200 ppm yucca powder supplementation to the diet.  相似文献   
129.
This study involved 14 ostriches of both sexes between 3 and 24 mo of age. Some hematologic and biochemical parameters were studied in animals with stomach impaction. Clinical examination of the birds revealed anorexia, emaciation, decreased defecation, listlessness, separation from the flock, and recumbence. The total number of leukocytes (10.4 x 10(3) mm3), the concentrations of serum glucose (166 mg/dl), and total protein (2.4 g/dl) decreased; serum creatine phosphokinase (1240 U/L) and alkaline phosphatase (598 U/L) increased; whereas no changes were found in the concentrations of calcium, phosphorus, magnesium, zinc, and copper. Medical treatment was initiated in 13 animals; six of them recovered and seven birds died. Necropsy revealed edema, erosions, and hemorrhagic ulcers in the stomach of the dead birds. Foreign bodies such as sand; stone; pieces of wood, glass, and plastic; and metallic objects were encountered in the stomach at the necropsy. In one bird, metallic foreign body was diagnosed and the bird was referred to surgery. Under stress factors, ostriches tend to eat foreign material; therefore, adequate housing, nutrition, and care are crucial in prevention of stomach impaction.  相似文献   
130.
The effects of different dietary levels of zinc and vitamin A on tissue mineral accumulation and histopathological alterations were examined in laying hens. For this purpose, 130 Hisex brown laying hens aged 56 weeks were divided into two main groups. Each group of hens were fed on diets supplemented with two different levels of vitamin A (0-10,000 IU kg(-1)). Then, laying hens in both of the main groups were subdivided into five treatment groups given different levels of zinc (0, 25, 50, 100, and 200 mg kg(-1)) for 12 weeks. Dietary additions of zinc and/or vitamin A did not significantly affect the zinc concentrations of the pancreas, liver, gizzard, thyroid, and copper concentrations of the pancreas, gizzard, and thyroid. The group fed the highest zinc (200 mg kg(-1)) in the diet had twofold iron concentration in their thyroid tissue compared to the concentration of the control group receiving no extra zinc. Histopathologically, there was slight oedema, degranulation, and vacuolation in exocrine cells and some fibrotic areas in the pancreas and reduced follicular size. Follicular cell hypertrophy and hyperplasia occurred in the thyroids, and gizzard erosions were seen in some cases.  相似文献   
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