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91.
生物质混燃发电政策研究   总被引:1,自引:0,他引:1  
生物质混燃发电技术是一种重要的生物质发电技术,与生物质直燃发电技术相比,有着投资少、建设周期短、对原料价格控制能力强等优势,在欧洲有着较多的应用实例,但是在我国的应用非常有限。本文介绍了生物质混燃发电技术的发展现状、项目设计时要求注意的问题、国内外对生物质混燃发电项目的政策,分析了我国生物质混燃发电的发展障碍和解决方案,并提出了促进生物质混燃发展的意见和建议。  相似文献   
92.
Two strategies for crossbreeding of indigenous and exotic cattle for milk production in the tropics, viz. rotational crossing and formation of a composite breed, have been compared. Genetic considerations suggest that rotational crossing would lead to somewhat better dairy performance, mainly because of more heterozygosity. Predictions based on the performance of adjacent genetic groups as obtained from a comprehensive literature review point in the same direction. Rotational crossbreeding depends on a continuous introduction of bulls of both parental breeds. The herd will consist of 2 (or more) genetic groups, which might be inconvenient for breeding arrangements, but provides more flexibility. The system requires good organisation and is most suitable in large farms. In small scale dairying the composite breed strategy is the most practical approach to dairy cattle breeding in the tropics.  相似文献   
93.
OBJECTIVE: To investigate the understanding and expectations of defendants referred to Valkenberg Hospital for 30-day observation. DESIGN: Defendants referred for 30 days of psychiatric assessment were surveyed by means of a semi-structured interview within 3 days of admission. PARTICIPANTS: One hundred consecutive referrals from the Western, Northern and Eastern Cape were considered; 88 were eventually entered into the study. RESULTS: All defendants were generally ignorant of the reasons for referral, but had a good understanding of court procedure and wrongfulness. Mentally ill subjects differed only in their not being able to distinguish between a guilty/not guilty plea. Most did not have legal representation, did not personally request the assessment and denied guilt of the alleged offence. CONCLUSIONS: Mental illness affects triability but not necessarily criminal responsibility. Disturbingly, most defendants were without legal representation and were unaware of the purpose, implications and possible outcomes of psychiatric observation. It is imperative that the legislation governing these aspects be reviewed.  相似文献   
94.
The effect of a range of surface treatment processes on the properties of a group of tool steels has been examined. In this first part attention is concentrated on the various nitriding processes.  相似文献   
95.
The application of a Silon pouch usually indicates a desperate if not impossible situation in which the abdominal contents cannot be returned to the abdominal cavity and therefore require some type of covering. Since 1968, we have had experience with 55 Silon pouches in infants and children. Almost all of these pouches were applied to newborns. There were 22 deaths in this series (40%), although 12 of these deaths were in the diaphragmatic hernia group and were almost all due to respiratory failure unrelated to the pouch itself. There were nine deaths in the gastroschisis and omphalocele group (28%) and in all these instances infection (especially Candida) was the underlying cause. While much debate exists as to how the Silon pouch should be handled after its application our series demonstrated that the longer it stayed in place the greater the chance of infection. Furthermore if broad spectrum antibiotics were used for a prolonged period of time, Candida overgrowth of the pouch followed by Candida sepsis and death were almost inevitable.  相似文献   
96.
Traumatic rupture of the aorta. A five-year experience   总被引:1,自引:0,他引:1  
In the five-year period ending in October, 1975, 31 consecutive patients with traumatic rupture of the thoracic aorta underwent surgery at the University of Maryland Hospital or the Maryland Institute for Emergency Medicine. All cases were confirmed by preoperative aortogram. Rupture was confined to one or more sites in the descending thoracic aorta at or distal to the origin of the left subclavian artery. The age was a mean of 26 years. Operation was done within an average of 18 hours after injury. Significant nonthoracic injuries were present in every case. Six patients with positive findings on peritoneal lavage underwent exploratory laparotomy prior to thoracotomy because of shock. Surgical repair was done by use of left heart bypass in 2 cases (one death), a passive aorta-aorta shunt in 23 cases (5 deaths), and without shunt or bypass in 6 cases (no deaths). An end-to-end tubular Dacron graft was used to reconstruct the aorta in all but one patient. Over-all survival rate was 25 of 31 patients (81 per cent). Paraplegia developed in one patient and renal failure in 3 patients (2 deaths) in the aorta-aorta shunt group. Hypertension was present in 18 (72 per cent) of the survivors. Palsy of the left recurrent laryngeal nerve persisted in 8 (32 per cent) of the survivors. Two of the deaths were related to technical problems of the shunting procedure and 2 to intrapleural exsanguination before proximal aortic control could be achieved. Complications and blood loss were reduced in the group with no shunt. The series lends support to the rigorous aortographic search for ruptured thoracic aortas in trauma patients with widened mediastinum. Once experience has been gained with shunting techniques, tears of the descending thoracic aorta may be safely repaired without shunt if done expeditiously.  相似文献   
97.
98.
A tadpole of bullfrog, Rana catesbeiana, is originally covered with the larval skin over its entire body. Drastic changes arise in both the epidermis and the subcutaneous connective tissue at an early developmental stage, producing the precursor of adult type skin (pre-adult skin). It was found that calcium is a useful probe to detect the region where the precursor formation has occurred because its deposition in the upper part of subcutaneous collagen bundles coincides with the appearance of the pre-adult skin. Whole-mount in situ staining of tadpoles with alizarin red S revealed the initiation site of the premetamorphic transformation of the larval skin into the adult precursor and its ensuing region-dependent expansion. The pre-adult skin first emerged at TK II to III (TK, Taylor and Kollros staging) t lateral sides of the body, which led us to postulate that 'the center for premetamorphic skin transformation' is formed at the specific site in this region. This center moved dorsally and then ventrally, then reached to the most proximal region of the tail, yielding a unique sequential conversion pattern by around TK V when the conversion was completed in the trunk. The present study also visualized the process of the hindlimb skin transformation.  相似文献   
99.
Radiofrequency (RF) energy has many advantages in thermal tumor ablation protocols. With the recent development of open MRI systems, interventional MRI procedures, including thermal ablation, have become the focus of great research interest. However, the significant interference between RF generators and MR imagers has prevented simultaneous imaging and RF ablation and, until now, has limited the role of RF-based thermal therapy in interventional MRI. Here, a simple switching circuit designed with consideration of patient safety provides compatibility between open MRI systems and RF thermal lesion generators. The experimental results show that the switching circuit allows imaging during RF ablation and opens new opportunity for MR-guided thermal therapy.  相似文献   
100.
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