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1.
用巯基苯并噻唑(NaBMT)作捕收剂对来自赛尔西尼(Salsigne)矿床的两种难选含金矿石试样进行了浮选试验.结果表明,用KAX(钾黄药)(25%)和NaMBT(75%)的混合药剂取代常规的混合捕收剂,即使其用量较小,仍可使毒砂、尤其是金的浮选得到明显的改善.浮选选择性相回收率的改善,必须是在有关作业协同的有效作用下进行,这些作业为,强力浮选把毒砂和金回收到粗精矿中,再对粗精矿进行有效的精选和单体石英的弱浮选.  相似文献   
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本研究由MOD支持,评估了有几个起爆点的爆炸成形弹丸,固定的参数为112mm弹径,铁质药型罩和炸药装药,这样做的结果是弹丸长度明显减小。通过一种数字和实验的方法研究了杵体弹的爆轰性能和空气动力学特性,观察爆轰波的相互作用,发现超压的作用保证了一个速度 2140m/s和122mm长的杵体弹,而炸药高度只有30mm。  相似文献   
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对计划用于冲击片雷管的快速高电流开关进行与时间有关的电阻测量。这种开关由铜-聚合物-铜叠层片构成,设计用于在受到爆炸驱动的铜飞片撞击后传导电。我们实验中使用的聚合物膜是Kapton(聚苯均四甲酰亚胺),预计这种膜在9GPa和9GPa以上的压力下具有冲击感应传导性。当这种开关中获得9GPa左右的冲击压力时,没有发现有明显的冲击传导作用。通过观察Teflon(聚四氟乙烯)膜开关同样的电性能进一步证实了  相似文献   
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The coevolution of genomics and proteomics has led to advancements in the field of diagnosis and molecular mechanisms of disease. Proteomics is now stepping into the field of obstetrics, where early diagnosis of pregnancy complication such as preeclampsia (PE) is imperative. PE is a multifactorial disease characterized by hypertension with proteinuria, which is a leading cause of maternal and neonatal morbidity and mortality occurring in 5-7% of pregnancies worldwide. This review discusses the probable molecular mechanisms that lead to PE and summarizes the proteomics research carried out in understanding the pathogenicity of PE, and for identifying the candidate biomarker for diagnosis of the disease.  相似文献   
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The application of the velocity of sound (VOS) technique to lamb carcasses in a previous study (Fisher & Page, 1986) measured composition at a hind limb and neck site but was not as precise as fat scores in predicting lean proportion. This study examines VOS measurements made at sites in the hind limbs and along the vertebral column in live sheep and carcasses. A group (A) comprising five breeds of males and females (n = 61) and a sub-group (B) of Scottish Blackface castrated males (n = 34) were studied, and the reciprocal velocity of ultrasound (RV) was measured on the live sheep immediately behind the shoulder and over the last rib using a fixed-distance transducer assembly operating at 5 MHz, and in the hind limbs at 2·25 MHz using the apparatus described by Miles et al. (1984). Corresponding measurements were made on the carcasses which were classified by a Meat and Livestock Commission fatstock officer and then dissected. Standard deviations of lean proportion were 4·48% (A) and 3·39% (B). The residual standard deviations (rsds) for groups A and B respectively were obtained using the following predictors: live mass (LM) 4·27% and 2·96%; LM + breed (B) 3·08% (group A only); LM + mean RV 2·36% and 2·07%; LM + B + mean RV 1·99% (group A only). Using carcass measurements: carcass mass (CM) 4·25% and 2·90%; CM + MLC fat score 2·99% and 2·12%; CM + RV last rib 2·89% and 2·02%. These data show that VOS measurements through dorsal sites of live sheep provide encouragingly precise estimates of carcass lean proportion. For carcasses, dorsal sites provide a less precise estimate of carcass lean but when carcass mass is included in multiple regression the precision of the correlation is comparable with that of multiple regression of fat score with carcass mass.  相似文献   
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Pervious pavements are sustainable urban drainage systems already known as rainwater infiltration techniques which reduce runoff formation and diffuse pollution in cities. The present research is focused on the design and construction of an experimental parking area, composed of 45 pervious pavement parking bays. Every pervious pavement was experimentally designed to store rainwater and measure the levels of the stored water and its quality over time. Six different pervious surfaces are combined with four different geotextiles in order to test which materials respond better to the good quality of rainwater storage over time and under the specific weather conditions of the north of Spain. The aim of this research was to obtain a good performance of pervious pavements that offered simultaneously a positive urban service and helped to harvest rainwater with a good quality to be used for non potable demands.  相似文献   
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We describe a high-performance associative-memory system that can be implemented by means of an optical disk modified for parallel readout and a custom-designed silicon integrated circuit with parallel optical input. The system can achieve associative recall on 128 × 128 bit images and also on variable-size subimages. The system's behavior and performance are evaluated on the basis of experimental results on a motionless-head parallel-readout optical-disk system, logic simulations of the very-large-scale integrated chip, and a software emulation of the overall system.  相似文献   
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