从选铁尾矿中回收白钨选矿试验研究

对某选铁尾矿中的白钨进行了综合回收试验研究。根据试料性质,采用了弱磁选-重选-强磁选、弱磁选-重选、弱磁选-重选-浮选等3种方案进行白钨选矿试验,最终确定弱磁选-重选-浮选工艺。试验结果为铁精矿品位Fe65.89%,回收率22.07%,钨精矿品位WO351.64%,回收率为10.94%的分选指标。     

某难选黑白钨共生矿试验研究

某黑白钨共生矿中富钙、富镁的脉石矿物含量高,严重影响了钨矿物的回收利用。为了解决该技术难题,原矿经硫化矿浮选、磁选后对钨给矿(WO3 0.48%)进行试验研究,采用改性水玻璃、硝酸铅,螯合类捕收剂GYB和改性脂肪酸类捕收剂GYR组合进行粗选获得的黑白钨混合粗精矿,采用改进型彼得洛夫法-添加调整剂NC、NF、水玻璃和捕收剂GYR,进行加温精选分离,加温精矿经酸浸得白钨精矿,加温尾矿经摇床得重选黑钨精矿,摇床尾矿经浓缩添加调整剂NA、改性水玻璃和硝酸铅,组合捕收剂GYB和GYR得浮选黑钨精矿。小型试验获得指标:WO372.21%的白钨精矿,回收率59.08%。WO3 47.92%的重选黑钨精矿,回收率14.15%。WO3 55.72%的浮选黑钨精矿,回收率6.33%。钨的总回收率达79.56%。     

钨矿山尾矿综合利用试验研究

通过对13个钨矿选厂的尾矿进行综合利用选矿试验研究,采用浮选-重选和浮选-磁选-重选联合流程,可选得钨粗精矿平均含WO320%以上,回收率17%～37%,硫化矿中钼平均品位4.19%,回收率67.60%,铋平均品位2.78%,回收率41.36%,为矿山企业保护和合理开发利用钨尾矿二次资源提供了技术支持和储备。     

微细粒级钨细泥选矿试验研究

某钨矿主干流程为重选工艺,钨回收率小于63%,约30%的钨矿物损失于原生钨细泥和由于过粉碎产生的次生钨细泥中.为了提高资源利用效率,对该企业重选尾矿中的微细粒级钨细泥资源进行了高梯度磁选、浮选、离心机重选对比试验研究以及＂浮选-离心机重选＂联合流程试验研究.采用＂浮选-离心重选＂联合流程,开路试验获得的钨精矿品位达到32.14%,回收率达到73.51%,试验获得了良好的指标,对微细粒钨细泥的回收具有借鉴意义.     

微细粒级钨细泥选矿试验研究

某钨矿主干流程为重选工艺,钨回收率小于63%,约30%的钨矿物损失于原生钨细泥和由于过粉碎产生的次生钨细泥中.为了提高资源利用效率,对该企业重选尾矿中的微细粒级钨细泥资源进行了高梯度磁选、浮选、离心机重选对比试验研究以及"浮选-离心机重选"联合流程试验研究.采用"浮选-离心重选"联合流程,开路试验获得的钨精矿品位达到32.14%,回收率达到73.51%,试验获得了良好的指标,对微细粒钨细泥的回收具有借鉴意义.     

二河沟难选白钨矿选矿工艺流程研究

本文介绍了文山二河沟难选白钨矿的矿石特性及其对选矿工艺的影响,进行了细磨后重选预先富集丢除尾矿、粗精矿磁选除铁、浮选除硫、重选进一步提高钨精矿品位的试验。在此基础上提出了采用重磁浮联合选矿工艺流程处理该矿石。     

某钨选厂粗精矿分选试验研究

某钨选厂粗精矿采用分级粗粒枱浮硫化矿、细粒浮选硫化矿,浮选尾矿采用磁选优先选出一部分黑钨单体,分选尾矿磨至目的矿物单体解离后,先浮选硫化矿,再浮选白钨,重选分离锡石,所有硫化矿集中进行铜硫分离的工艺对粗精矿中的目的矿物进行分选。通过该工艺流程有效地分离了粗精矿中的钨、锡、铜、硫。获得钨精矿WO3品位≥60%,回收率≥88%,铜精矿Cu品位≥24%、回收率≥90%,锡精矿Sn品位≥45%、回收率≥70%。     

湖南某难选黑白钨矿中的白钨浮选试验研究

为解决湖南某黑白钨矿中以萤石为主的脉石对白钨浮选干扰较大的问题,对该黑白钨矿通过浮选先回收钼、铋硫化矿,浮选尾矿经弱磁除铁,然后弱磁选尾矿经高梯度磁选机磁选得到的非磁产品作为白钨给矿(WO3 0.33%)进行浮选,采用调整剂TT+水玻璃和新型捕收剂TAB-3进行白钨矿粗选、NT+水玻璃进行白钨加温精选、白钨加温精矿经酸浸后取得品位为72.59%WO3,WO3回收率为70.64%的白钨精矿。     

广东某低品位黑白钨混合矿选矿试验研究

随着钨资源不断开发利用,钨矿品位逐年下降,造成采选成本高,选矿难度大,尤其黑白钨混合矿综合利用率较低。为了解决如何高效回收利用这类钨矿山资源的难题,针对某矿山原矿WO₃含量为0.15%的钨矿石进行选矿试验研究。研究表明,采用强磁选-重选-浮选联合工艺,强磁选-重选可获得黑钨摇床精矿和黑钨摇床中矿,其WO₃含量分别为56.76%和21.08%,回收率分别为20.43%和5.20%;强磁选矿尾矿分级溜槽重选和摇床重选可获得白钨摇床精矿,其WO₃含量为58.34%,回收率为37.33%;摇床中矿和细泥归队集中浮选可获得白钨浮选精矿,其WO₃含量为65.04%,回收率为16.91%;最终黑白钨精矿及钨中矿产品中钨回收率合计为79.87%。该工艺可以获得较好的钨选矿指标,且选矿经济效益明显,可实现钨的高效回收,为此类资源的开发利用提供借鉴。     

从河南栾川浮钼尾矿中综合回收白钨矿的生产实践

为充分合理地利用矿产资源,提高资源利用率,增加企业效益,在直接从浮钼尾矿中浮选回收白钨矿试验取得成功的基础上,实现了从尾矿中回收白钨的工业生产。当浮钼尾矿白钨矿品位为0.060%左右时,经过粗选段的一粗一扫和白钨粗精矿加温精选段的五次精选三次扫选,产出最终精矿品位达25%以上,实际回收率在62%左右。     

Career by choice, not by chance

OBJECTIVE: To analyze the effects of a prospective peer review program on diagnostic accuracy in a routine cytopathology laboratory. STUDY DESIGN: For the study, 4,836 consecutive cases subjected to fine needle aspiration cytology (FNAC) over a one-year period were used. Nine pathologists performed both reporting and peer review functions. Disagreements were classified into "diagnostic errors" and "diagnostic discrepancies," depending on their impact on patient care. The effect of this review on turnaround time was statistically analyzed. A retrospective review of 4,025 cases from the preceding year was performed for comparison. RESULTS: Sixty-six cases with diagnostic disagreements were detected by prospective review. There were 28 diagnostic errors and 38 diagnostic discrepancies. The initial turnaround time for diagnostic FNAC in 90% of total cases was < 24 hours; mean delay for the remainder was 3.3 days. Prospective peer review added a further delay of 1 and 1.5 days, respectively. The number of diagnostic disagreements was significantly higher in the retrospective review (P < .01). CONCLUSION: Prospective peer review of diagnostic FNAC resulted in improved accuracy of diagnosis and reduced potential for inappropriate therapy; however, turnaround time was significantly increased.     

Acute poisoning by beta-blockers and by calcium inhibitors

beta-blockers and calcium-channel inhibitors are frequently used for self-poisoning. Propranolol and verapamil, the leading drugs in each pharmacological class, are the most toxic. They interfere with intracellular calcium concentration in muscles. Circulatory insufficiency may be due to vasodilatation, myocardial depression or severe bradycardia. If one respects a specific sequence for administration, the usual antidotes (glucagon, calcium salts, isoprenaline, epinephrine) are usually efficient. One must not underestimate the risk of worsening of an intoxication that is seen at the early stage, that occur in an old person or in a patient with heart disease, or that depress ventilation. Hence, it is important to monitor and treat these intoxications in an intensive care unit.     

Psychologist by training, bureaucrat by practice.

Communication with Congress; state and local officials; and numerous professional, advocacy, scientific, and public interest groups is essential to working on mental health and substance abuse issues at the federal policy level. The public administrator's work is diverse and fast-paced, involving issue analysis, proposal development and justification, public speaking, and dialogue with advocacy and policy analysis groups. Making decisions that will serve the public good in the long run is the core of the job. As the competition for resources escalates, the perspectives' of consumers of services and their families are important to guide decisions. In a career that is based on interactions, relationships, judgments, and evaluation of multifaceted issues, success is measured by a reputation for fairness and by accomplishments that are based on numerous individual decisions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lipopolysaccharide-induced interleukin 8 production by human whole blood is enhanced by epinephrine and inhibited by hydrocortisone

To determine the effect of epinephrine and hydrocortisone on lipopolysaccharide (LPS)-induced interleukin 8 (IL-8) production, human whole blood was stimulated with LPS in the presence or absence of these stress hormones. Epinephrine caused a dose-dependent increase in LPS-induced IL-8 production, which was mediated exclusively via beta-adrenergic receptors, as reflected by the facts that beta (but not alpha) receptor blockade reversed the epinephrine effect and beta (but not alpha) receptor stimulation reproduced the epinephrine effect. Further, elevating cellular cyclic AMP (cAMP) concentrations, a known effect of beta-adrenergic stimulation, by addition of dibutyryl cAMP also enhanced LPS-induced IL-8 production. Epinephrine-induced upregulation of IL-10 production masked an even more pronounced stimulating effect of this hormone on IL-8 synthesis, as indicated by the finding that the extent of IL-8 upregulation was greater in the presence of anti-IL-10 than in the absence of anti-IL-10. Hydrocortisone dose-dependently inhibited LPS-induced IL-8 production and reversed epinephrine-induced enhancement of IL-8 production. Epinephrine and hydrocortisone have opposite effects on IL-8 production, which may be relevant for the understanding of endogenous and therapeutic stress hormone influences on IL-8 mediated inflammation.     

Characterization of immature B cells by a novel monoclonal antibody, by turnover and by mitogen reactivity

The transit of immature to mature sIgM+ B cells, the life span, maturation kinetics and response to polyclonal activators have been analyzed with the help of a new mAb (493), that distinguishes immature, 493+ from mature, 493 B cells in a variety of mouse strains tested. Analysis of the turnover of immature 493+ B cells by bromodeoxyuridine (BrdU) labeling kinetics indicate that only 10-20 % of the cells reach the spleen as immature 493+ cells. The life span of 493+ B cells in bone marrow and spleen is around 4 days. BrdU chase experiments show that most of the immature cells in spleen enter the pool of mature, 493+ B cells where they gain a longer life span of 15-20 weeks. Immature and mature B cells respond equally well to LPS stimulation; anti-CD40, however, stimulates mature B cells better than immature B cells. IgM cross-linking of mature B cells results in proliferation, while it induces apoptosis in immature B cells. This apoptosis of immature cells can be inhibited by costimulation with anti-CD40 or by overexpression of bcl-2. We speculate that Ig receptor ligand-mediated apoptosis (negative selection) plays a major role in the transit of immature B cells from bone marrow to spleen, but only a minor role in the transit from immature B cells to mature B cells in the spleen.     

论会计法治与会计德治

坚持"依法治国"和"以德治国"相结合的治国方略,是党中央在全面而深刻地总结古今中外治国经验的基础上得出的科学结论.毫无疑问,这对于加强我国会计工作的"法治"和"德治",充分发挥会计的职能作用,也有着特别重要的指导意义.籍此<会计法>颁布实施20周年之际,就会计教育与会计法治、会计德治问题谈谈我们的观点,以纪念<会计法>颁布实施20周年.     

Inhibition of pyruvate oxidation by skeletal muscle mitochondria by phenylpyruvate

1. Phenylpyruvate inhibits pyruvate plus malate oxidation in human and rat skeletal muscle mitochondria in state 3 and in the uncoupled state, it has, however, no effect in state 4. 2. Inhibition by phenylpyruvate of pyruvate oxidation by intact uncoupled rat muscle mitochondria was competitive, with the Ki value about 0.18 mM. 3. It is suggested that the inhibition of pyruvate oxidation is due to the action of phenylpyruvate on muscle pyruvate dehydrogenase, and is the principal cause of the elevated concentration of pyruvate and lactate in blood plasma of phenylketonuric patients.