生产中控制介耗的经验探索

介绍火烧铺矿选煤厂降耗的经验。     

某白钨矿重介质旋流器抛尾可行性试验研究

某白钨矿具有WO3品位低、嵌布粒度细的特点,分选过程中大量脉石矿物的存在导致入磨量大,能耗、药剂消耗高,且产生大量细粒级尾矿.采用重介质旋流器抛尾工艺进行试验研究,通过重介质旋流器抛尾工艺,最终实现抛废率为43.56％、WO3金属损失率5％的良好指标.试验结果表明重介质旋流器抛尾工艺具有可行性.     

重介质旋流器在锂辉石选矿中的应用

针对锂辉石矿物嵌布粒度粗,细碎后易解离的特点,结合锂辉石矿物与石英、长石等脉石矿物存在明显密度差异等特征,采用重介质旋流器对不同地区锂辉石矿进行了重介质试验。结果发现,不同地区锂辉石均可通过重介质选矿,提前获得高品质锂辉石精矿产品,同时抛除大量尾矿产品,极大降低入磨量,显著降低了锂辉石选矿成本,提高选厂经济效益。     

重介质旋流器的研究与应用

通过参数试验研究与工业应用，阐明了重介质旋流器的结构特征和选别特点。指出，分选效果的好坏取决于结构参数与矿石中轻、重矿物比率的适应程度，在工艺设计时，应当了解矿石的丢废率变化特性，以最低丢废率进行参数设计。最低丢废率应当大于５０％，才能获得稳定的技术指标和良好的经济效益。     

关于对火铺矿选煤厂350万t/a扩能改造的初步构想

介绍火铺矿选煤厂的现状及存在的瓶颈制约问题，与配套矿井进行同步扩能改造的必要性和紧迫性；根据矿井采煤方法及煤质特性并结合选煤厂现有工艺等实际情况，提出了选煤厂扩能改造的初步构想：即采用原煤预排矿——三产品全煤重介——煤泥直接浮选——尾煤泥压滤联合工艺流程，并对该工艺流程进行了详细阐述，提出了本次技改存在问题。     

某铅锌矿重介质旋流器选矿工艺研究

针对省内某铅锌矿,从试样工艺矿物学研究入手,先介绍了重介质旋流器选矿的工艺流程和加重剂的物理化学特性,然后通过详细的条件试验,确定了适宜的工艺参数和工艺条件,并以半工业试验的规模进行了验证试验,获得了满意的分选指标。     

潘家冲铅锌矿重介质旋流器选矿工艺研究

本文介绍了潘家冲铅锌矿石的重介质选矿半工业试验,详细地研究了黄铁矿作为分选介质的物理化学特性,查明了重介质选矿过程中诸工艺参数之间的相互关系,推荐了适合该矿石特点的工艺流程,为低品位铅锌矿山提高经济效益探明了一条有效途径。     

滇池地区中低品位磷矿石选矿工艺的新探索

论述了滇池地区中低品位磷矿石选矿工艺的新思路,提出重-浮联合流程,采用高效的水介质旋流器和矮柱浮选槽,实现了更经济合理地回收胶磷矿;精矿品位及其中杂质含量均达到国家酸法二级标准,精、尾矿水排放达到了GB8978-88污水综合排放二级标准.为滇池地区乃至省内同类型的中低品位磷矿石的开发利用提供了良好前景.     

新的重介质三产品水力旋流器

苏联乌克兰煤选矿科学研究院等单位研制了一种新的ГТ-750/500型三产品串联重介质水力旋流器(见图).其技术特性见表1.为评价该设备,曾在各种不同的生产条件下进行了平行的比较试验。在某一选厂中分选了煤粉(普通煤的筛下产品),     

重介质选煤工艺中磁铁矿粉损耗的考查研究

通过对月亮田矿重介质选煤厂最终产品带介损耗和磁选尾矿流失介耗考查，以及试验室模拟磁选试验研究表明：在正常情况下，筛上产品带介损耗较低，一般不超过1．0kg／t原煤，磁选矿尾矿流失的磁铁矿粉却高达2．65kg／t原煤，其中-5μm回收效果最差，粒级回收率仅有80％，而 5μm粒级回收率均高达99％。得出：超细或极细粒级磁铁矿粉对磁选回收十分不利。     

Changes in the ultra-fine structure of capillaries of the embryonic brain in the presence of schizophrenia in the mother

The report is concerned with a study of fine structures of brain capillaries in 9 embryos received during medical abortions from schizophrenic mothers. The authors established some traits in the ultrastructure of endothelial cells in most of the studied cases--an increase of the surface of endothelial cells at the expense of a tortuosity of their plasmatic membranes and a formation of growths, vacuolization of the cytoplasma. There were also some changes in the structure of basal membranes. In 2 cases there were also peculiar pathological changes in the vascular endothelium: granules of an unknown nature in the endothelial cells and a focal lysis of the plasmatic membranes of endothelial cells.     

不同除草剂在直播冬油菜田的除草效果研究

[目的]验证不同除草剂的除草效果,为直播冬油菜田的杂草防除提供借鉴.[方法]使用不同剂量25%胺苯磺隆可湿性粉剂和10.8%高效氟吡甲禾灵乳油在直播冬油菜田间进行单用和混用除草试验.[结果] 25%胺苯磺隆可湿性粉剂在冬油菜4～5叶期使用可以有效防除田间的阔叶杂草;25% 胺苯磺隆可湿性粉剂18.0～22.5 g/hm<'2>+400 ml/hm<'2>的10.8%高效氟吡甲采灵乳油可以有效防除油菜田间的阔叶和禾本科杂草,总防效达90%以上,且可以比人工除草节省成本1 100元、hm<'2>.[结论] 25%胺苯磺隆与10.8%高效氟吡甲未灵乳油混用可以更好地防除冬油菜田间杂草.     

Simulation of the solidification of the melt in the Vanyukov furnace in the case of emergency stoppage

A mathematical model of the Vanyukov furnace, which makes it possible to predict the behavior of an object in the emergency operational mode (upon the disconnection of the oxygen supply) and develop an effective system of additional heating which damps the consequences of the emergency mode and lowers the costs for the renovation of the furnace operation, is created. It is shown how solidification upon cooling the furnace with time is simulated using the enthalpy and porosity method. The mathematical model is adopted for existing production conditions, which are weakly defined. The energy characteristics of the mode for the solidifying furnace bath, which ensures its holding for a long time in the ready state to rapid firing, are found. Thus, the problem of excessively expensive furnace firing after prolonged production stoppage is solved in the conjugated statement with a calculation of the heating system of the overbath space.     

Variations in the relationship of the major vessels of the left coronary groove in the dog

The anatomic relationship of the 2 major vessels of the left coronary groove was studied in 140 dogs. Five basic patterns of disposition were observed: 1) circumflex artery superficial from its origin to the caudodorsal cardiac margin, coronary vein deep and not visible (22%); 2) coronary vein superficial from the ventral interventricular septum to the caudodorsal cardiac margin, circumflex artery deep and not visible (15%); 3) circumflex artery and coronary vein both superficial and running parallel with each other along the groove (8%); 4) coronary vein crossing circumflex artery at some point along the groove (44%); and 5) circumflex artery crossing coronary vein at some point along the groove (11%). These variations were found to influence certain experimental modifications of the left circumflex blood flow in the dog.     

Errors in the surgery of the testicle in children

The study was made of labyrinthine changes induced by lasix dehydration. Changes indicative of Meniere's disease were identified at comparison of the findings obtained by audiological lasix test, caloric optokinetic reactions. Four types of the nystagmic response in the bithermal lasix-test were determined. These reactions are helpful for more precise staging of the disease.     

Role of the subthalamo-nigral input in the control of amygdala-kindled seizures in the rat

The substantia nigra pars reticulata (SNpr) is a critical site for the control of epileptic seizures. Potentiation of the inhibitory GABAergic input from the striatum to the SNpr suppresses primary or secondary generalized seizures in the rat. The purpose of this study was to examine the possible involvement of the excitatory glutamatergic input from the subthalamic nucleus to the SNpr in the control of both the electroencephalographic and the motor components of amygdala-kindled seizures in the rat. Microinjections of either an N-methyl-D-aspartate (NMDA) antagonist in the substantia nigra or a GABAA agonist in the subthalamic nucleus, significantly reduced motor seizures but did not modified the afterdischarges. These results provide evidence for the involvement of the subthalamo-nigral projection in the modulation and the propagation of the motor components of amygdala-kindled seizures.     

Regional differences in the distribution of catalase in the epithelium of the ocular lens

The objectives of this study were to develop a system to calculate the economic consequences of accidents and to account for the economic consequences of all accidents during 1 year in a district. A total population injury survey was done in an area with a population of over 41,000. All accidents (N = 4926) occurring within a 12-month period and requiring medical care were noted. The costs (calculated at 1991 prices) to the health care service (outpatient care, including primary health care and hospital care) were SEK 23.7 million (US $3.59 million), to trade and industry SEK 79.7 million (US $12.08 million), and for health insurance SEK 9.1 million (US $1.38 million). The cost for society of uninsured people is not possible to estimate using loss of production. However, the time lost from "normal activities" was registered. If this time is valued at the same price as working hours, a welfare cost of SEK 43.1 million (US $6.53 million) should be added. In a forthcoming paper, an assessment of the cost-effectiveness of interventions against accidents will be published.     

A change in the state of neurons of the arcuate region of the hypothalamus in different stages of the sexual cycle in rats

With the help of microionophoretic stimulation of individual neurons of the arcuate region of the hypothalamus and the registration of its activity, changes in the sensitivity to dopamine during several stages of the sexual cycle of rats was studied. It was shown that in the 1st half of the day of proestrus the majority of neurons of the arcuate region, in correspondance to the increase in the level of estrogens in the blood plasma during this phase of the cycle, were activated by microionophoretic injections of dopamine. In the 2nd half of the day of proestrus, when the level of estrogens is minimal, and in the Diestrous-2 stage, it was observed that among registered neurons, those activated by dopamine were the most inhibited.     

On the role of self-excitation in the development of topographic order in the visual system of the frog

A two-level model is presented for explaining the development of the topographically ordered retinotectal connections of the visual system of the frog. The columnar structure of the tectum were taken into account explicitly. Simulations suggest that the self-excitatory intracolumnar connections play an important role in the formation of the topography. In the case of self-excitation the system is able to recognize the topology of the visual field by the continuity of the object's movement.     

The role of the forestomachs in the adaptation of the alimentary function in ruminants

Dietary character of ruminants in the north is principally different between "nonselective" (cattle, sheep) and "selective" (reindeer, moose) species. Due to the developed polyfunctioning, forestomach in ruminants, primarily rumen and reticulum, are involved in the homeostasis formation in enteral and interior mediums, nutrients deposition and recirculation. That provides efficiency in utilization of deficient in nutrients forage and body reserves of wild ruminants during the winter. The original functional organization of absorption processes and nutrients recirculation across the multilayer epithelium of forestomach also promotes realization of the two levels metabolism during the year and adaptation of wild ruminants to season dynamics of nutrition.