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61.
孙立东 《断块油气田》2012,19(6):681-685
松辽盆地北部深层断陷构造复杂,制约了断陷优选评价工作.依据沙河子组残留特征与演化规律,将深层断陷划分为“持续沉降型、改造叠合型、继承反转型、改造叠合反转型”4种类型.研究表明:复杂改造叠合型盆地经早期改造并残留下来,往往成为断陷主体或沉积中心,其烃源岩条件较好,同时早期构造活动产生了大量气源断裂,并使地层上倾或者削截方向直接与储集体接触,有利于天然气聚集;持续沉降型断陷盆地沉积环境稳定,有利于暗色泥岩发育,具有较好的源岩条件,后期改造作用弱,有利于天然气保存;将深层断陷划分为Ⅰ,Ⅱ,Ⅲ类勘探区,明确了近期风险勘探的有利区带.  相似文献   
62.
牛奶蛋白纤维的结构与性能   总被引:15,自引:0,他引:15       下载免费PDF全文
利用扫描电子显微镜观察了牛奶蛋白纤维的形态结构。结果表明,牛奶蛋白纤维是异形纤维,截面上有微孔,表面有凹槽;对牛奶蛋白纤维的X-射线衍射分析显示聚乙烯醇分子规则排列构成结晶部分,牛奶蛋白形成无定形区;测试和分析了牛奶蛋白纤维的吸湿、拉伸、摩擦等性能,结果表明牛奶蛋白纤维是集蚕丝和合成纤维优良性能于一身的纺织新材料。  相似文献   
63.
孔西潜山奥陶系原生油藏成藏时期探讨   总被引:8,自引:4,他引:8  
黄骅坳陷孔西潜山发现奥陶系(孔古3井、孔古7井)低产原生油藏和石炭-二叠系原生油气藏(孔古4井),油源对比结果证明,前者原油主要源于中奥陶统马家沟组灰岩,后者油气主要源于石炭系太原组及二叠系山西组煤系泥岩。根据孔古3井油藏的两期流体包裹体及储集层自生伊利石K-Ar年龄测定结果,油藏属两期成藏,第一期为晚三叠世(距今222.51~240.34Ma),第二期为第三纪,以晚第三纪为主。  相似文献   
64.
随着油厂规模的扩大,所用的压力容器和换热器的容积也随之增大,其密封性直接关系到蒸汽和溶剂的消耗,因此将氦检漏技术引入其检验,以保证容器的泄漏率符合要求。本文介绍了压力容器尤其是大容积容器氦检漏常用方法及其在工业生产上的应用。  相似文献   
65.
The objective of this study was to evaluate the effects of seven single nucleotide polymorphisms (SNPs) in Calpain 1 and Calpastatin genes previously associated with meat tenderness attributes in other cattle breeds in Korean Hanwoo cattle. The Hanwoo resource population was used to study association of 7 SNPs with beef tenderness, flavor, juiciness, intramuscular fat and shear force. In this association study, CAST:c.182A > G (+ 0.14, P = 0.04) and CAST:c.1985G > C (− 0.12, P = 0.02) had significant effects on juiciness, but no effects on other traits. In contrast, CAPN1:c.1589G > A was associated with meat tenderness (P = 0.01) and juiciness (P = 0.04). The CAPN1:c.1589G > A (Val530Ile) SNP marker displayed significant effect on the meat tenderness score which is strongly supported by molecular modeling of the CAPN1:c.1589G > A (Val530Ile) variant that inhibits CAST protein from binding more strongly than the wild-type protein, which may explain its effect on meat tenderness.  相似文献   
66.
牦牛酸乳分离发酵乳杆菌发酵豆浆的胃溃疡预防效果研究   总被引:1,自引:0,他引:1  
赵欣  骞宇 《食品科学》2014,35(17):236-240
以采自川西青藏高原的自然发酵牦牛酸乳样品中分离纯化得到的1 株发酵乳杆菌(Lactobacillusfermentum Zhao,LFZ)作为研究对象,探索比较其与商业用嗜热链球菌(Streptococcus thermophilus,ST)发酵豆浆的胃溃疡预防效果。通过利血平诱导胃溃疡小鼠模型,LFZ组小鼠的IL-6、IL-12、TNF-α和IFN-γ细胞因子低于ST组小鼠;血清生长抑素和血管活性肠肽水平高于ST组,胃动素和P物质水平低于ST组,且LFZ组小鼠胃溃疡面积也低于ST组小鼠。由此可知,Lactobacillus fermentum Zhao发酵豆浆的品质优于标准嗜热链球菌发酵豆浆,且其对胃溃疡有很好的预防效果。  相似文献   
67.
Responses to lipid supplementation differ between dairy breeds and genetic lines suggesting nutrition by genotype interactions. β-Lactoglobulin phenotype is associated with changes in yield and composition of milk. The response of cows with different β-lactoglobulin phenotypes to lipid supplementation has not been examined. Furthermore, we examined whether lipid supplementation alters milk protein composition. By using a randomized block design, we fed Holstein cows for 3 wk either a control diet containing 2.8% crude fat (n = 19) or an experimental diet that was supplemented with 4.2% tallow (n = 20). Before randomization, all cows were fed the supplemental tallow diet for at least 2 wk. Dry matter intake, body weight, milk yield, and milk composition were measured in the last week before and during the experimental period. Feeding supplemental tallow increased dry matter intake and yields of milk and milk components, including casein content, without decreasing milk component content or altering milk protein composition. On the low-fat control diet, cows with the β-lactoglobulin allele B had a greater milk and milk component yield than cows with the A allele, whereas no differences by β-lactoglobulin phenotype were observed in cows on the tallow supplement diet. Our results suggest that cows that differ in β-lactoglobulin phenotype respond differently to a low-fat diet and that feeding cows 4.2% of additional tallow increases milk yield without affecting milk component content and milk protein composition.  相似文献   
68.
To estimate the prevalence of Coxiella burnetii in the dairy sheep population from the Basque Country (northern Spain), a study was carried out combining molecular and serological techniques. First, bulk-tank milk samples from 154 flocks belonging to the Latxa Breed Farmers Association were analyzed by PCR, with 22% of flocks testing positive for C. burnetii. Then, a selection of 34 flocks (7 PCR positive and 17 negative) was investigated for the presence of serum antibodies by ELISA test on 1,011 ewes (approximately 30 ewes per flock). A total of 8.9% of the animals were seropositive, 67.6% of the flocks had at least one seropositive animal, but only in 14.7% of them was seroprevalence greater than 25%. Older ewes showed a significantly greater prevalence (17.5%) compared with yearlings (7.5%) or replacement lambs (1.5%). A marginally significant association was found between seroprevalence and PCR detection of C. burnetii in bulk-tank milk. The widespread distribution of C. burnetii in the region advocates for the implementation of Q fever control strategies and highlights the potential risk of sheep as a reservoir and infection source for other domestic and wildlife species and the human population.  相似文献   
69.
A basal mixed ration supplying 36 mg of Zn/kg of dry matter (DM) was supplemented with 1 of 4 concentrates differing in level and form of dietary Zn. The concentrates were fed at 2 kg/cow per day and contained 300 mg of Zn/kg (to supply the total recommended level, according to NRC (2001); R) or 60 mg of Zn/kg (to supply 0.66 of the total recommended level; L), either supplemented as ZnO (I) or organically chelated Zn (O). Forty-four Holstein-Friesian dairy cows (12 primiparous and 32 multiparous), on average 31 d (SD ± 11.4) into lactation, were allocated to 1 of the 4 treatments. All cows remained on the treatment for 14 wk. The data was analyzed by ANOVA as a 2 × 2 factorial design. Dry matter intake averaged 23.5 kg/d and did not differ between treatments. Cows supplemented with organically chelated Zn at the recommended level of inclusion (RO) had a higher milk yield (37.6 kg/d) than those fed inorganic Zn at the recommended level (RI; 35.2 kg/d) or organically chelated Zn at the low level (LO; 35.2 kg/d), but was not different from those fed inorganic Zn at the low level (LI; 36.0 kg/d). Milk composition was unaffected by dietary treatment. Animals that received the low level of Zn (LI and LO) had higher somatic cell counts [3.97 and 3.93 versus 4.35 and 4.55 (loge) for RI, RO, LI, and LO, respectively] and milk amyloid A levels than those receiving the recommended levels (RO and RI). There was no effect of treatment on body condition score, body weight, or locomotion score. Hoof hardness improved over the duration of the study but there were no differences between treatments. Similarly, blood plasma mineral levels for Zn, Cu, Mo, and Fe were not affected by treatment, whereas there was a trend for increased ceruloplasmin levels in cows receiving the recommended compared with the low level of Zn, but there was no effect of mineral form. There was also no effect of treatment on superoxide dismutase activity or blood hematology. It is concluded that supplementing Zn at the recommended level reduced somatic cell counts and milk amyloid A levels, whereas supplementation in an organic form at the recommended level also increased milk yield.  相似文献   
70.
To improve the effectiveness of community-based breeding programs for increased milk production, the values of different udder measurements for predicting milk production traits during the milking period were assessed over 3 yr on 273 Awassi ewes. Machine milking of ewes began after weaning, 56 d after parturition, and continued until the milk yield of the ewes was <200 mL/d. Milk yield obtained by hand milking and milk composition were measured weekly, and days in milk, total milk yield, and total yields of protein, fat, and nonfat solids in milk were calculated for each ewe. On d 70 of milking, morphological traits of the whole udder (circumference, width, height, and length), udder cistern (height), and teats (length, width, and position score) were measured. On the same day, the milk yield of ewes was recorded by hand milking. Positive and moderate to strong correlations (r = 0.36 to 0.76) between udder circumference and width, teat width, and milk production traits of total milk yield, and total yields of protein, fat, and nonfat solids were found. However, a more accurate predictor of milk production traits was milk yield on d 70, as higher positive correlations between this variable and the milk production traits were found (r = 0.63 to 0.89). Nine farmers were invited to independently estimate the hand-milked milk yield performance of a sample of 169 ewes (d 15 to 45 of milking) by visually observing each ewe and making a subjective linear score (1 to 5). Their assessments were significantly correlated with milk yield on the day of the observation (r = 0.52), total milk yield (r = 0.50), and days in milk (r = 0.45). Considering the perception details provided by farmers concerning each of the subjective linear scores, it was found that most predictive linear udder measurements of udder circumference and width and teat width identified in this study were implicit in these scores. The predictive ability of the measurements studied have practical implications for community-based breeding programs involving improvement of milk production—not just in Syria, but in other countries in dry areas as well—because it is possible for experienced farmers to visually assess milk production of dairy ewes or take simple udder measurements with predictive value.  相似文献   
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