流化床与熔态还原法

一、前言自有炼铁生产以来,能源就成为确立工艺流程的决定因素,同时随着能源的变迁又不断推进新型流程的开发。在最初几个世纪里,作为可供使用的能源只有木材,这样就导致了木炭高炉的诞生。自十九世纪中叶开始使用烟煤,于是导致了炼焦炉和焦炭高炉的兴起。自廿世纪五十年代开始大最使用碳氢化合物,首先是石油,接着是价格比较低廉的天然气,从而导致气体直接炼铁法的工业应用,并作为焦炭高炉法的一种重要补充手段而得以发展。但自七十年代二次石油危机之后,从价格关系又重新向有利于煤的方向发展。为了适应这种社会经济环境的变化,在一些发达国家里相继地开发直接使用粉矿和普通煤(而不是炼焦煤)作为唯一能源来生产液铁的熔态还原法

MECHANISM AND EROSION EFFECT OF DEVELOPMENT OF SOIL CRUST OF LOESS

了解土壤结皮的发育特征及其对侵蚀的影响作用,是认识土壤侵蚀机理、建立精准侵蚀预报模型的重要理论支持之一。本文通过模拟降雨试验,探讨有无雨滴打击作用下黄土结皮的发育过程以及前期有无结皮时结皮侵蚀效应的动态特征。结果表明:(1)随降雨的进行,黄土结皮发生层容重、抗剪强度(含水率为20%)不断增加,30min内形成厚度约3～4mm稳定结皮层;(2)消除雨滴打击后,黄土结皮发育过程同有雨滴打击时类似,但程度减弱。雨滴打击同湿润作用对黄土结皮形成的贡献作用基本相当;(3)降雨初期有、无结皮处理抗剪强度差别大,随后急剧下降并趋同,因而黄土结皮影响抗蚀性的作用微弱,累积溅蚀量的差异主要由溅蚀起始时间的变化引起;(4)黄土结皮的存在明显的减少入渗、增加径流,但结皮效应随降雨进行逐渐消失。溅蚀效应的函数表达式为C=0.6670ln(t)-3.2459,结合溅蚀量的计算式,可较为准确地预测前期无结皮时某降雨历时的累积溅蚀量

紫色土表土结皮发育特征的试验研究

通过模拟降雨试验,探讨了紫色土表土结皮的发育特征。结果表明:有、无雨滴打击下,紫色土在30min内均形成稳定结皮层,厚度约7~8mm;淋移作用是紫色土形成结皮的主导作用,降雨打击使表土在降雨前期迅速形成致密薄层,抑制了淋移作用并使盖网处理的结皮容重略高;孔隙的剖面分布对入渗、抗剪强度有较大影响,表现在发生层总孔隙度低但分布均匀的盖网处理具有更强的入渗能力,且由于降雨初期未发生致密上层使其抗剪强度略低

重组人凝血因子Ⅷ治疗411例中重型血友病A患者的抑制物产生及安全性的回顾性分析

目的:分析国内血友病A患者接受第3代重组人凝血因子Ⅷ(FⅧ)替代治疗后FⅧ抑制物产生和相关安全性情况。方法:对411例重型和中型血友病A患者进行回顾性分析。结果:411例血友病A患者均为男性,46例仅接受百因止治疗,包括18例既往未接受过FⅧ治疗(PUP)和28例既往接受过FⅧ治疗(PTP);365例接受百因止与其他FⅧ制剂治疗,包括9例PUP和356例PTP。411例患者中13例(3.2%)报告了抑制物产生阳性,包括27例PUP中的3例(11.1%)和384例PTP中的10例(2.6%)。在365例接受百因止与其他FⅧ制剂治疗的患者中,分别有7例(1.9%)、36例(9.9%)和11(3.0%)报告了乙肝表面抗原阳性、乙肝表面抗体阳性和丙肝表面抗体阳性,同时有9例(2.5%)和1例(0.3%)报告了人类免疫缺陷病毒抗体和梅毒螺旋体抗体阳性。在46例仅接受百因止治疗的患者中,未见病毒学阳性结果。结论:中国血友病A患者接受百因止替代治疗总体安全且耐受性良好,抑制物发生率较低

Aripiprazole versus other atypical antipsychotics for schizophrenia

BACKGROUND: In most western industrialised countries, second generation (atypical) antipsychotics are recommended as first line drug treatments for people with schizophrenia. In this review we specifically examine how the efficacy and tolerability of one such agent - aripiprazole - differs from that of other comparable second generation antipsychotics. OBJECTIVES: To evaluate the effects of aripiprazole compared with other atypical antipsychotics for people with schizophrenia and schizophrenia-like psychoses. SEARCH METHODS: We searched the Cochrane Schizophrenia Group Trials Register (November 2011), inspected references of all identified studies for further trials, and contacted relevant pharmaceutical companies, drug approval agencies and authors of trials for additional information. SELECTION CRITERIA: We included all randomised clinical trials (RCTs) comparing aripiprazole (oral) with oral and parenteral forms of amisulpride, clozapine, olanzapine, quetiapine, risperidone, sertindole, ziprasidone or zotepine for people with schizophrenia or schizophrenia-like psychoses. DATA COLLECTION AND ANALYSIS: We extracted data independently. For dichotomous data we calculated risk ratios (RR) and their 95% confidence intervals (CI) on an intention-to-treat basis based on a random-effects model. Where possible, we calculated illustrative comparative risks for primary outcomes. For continuous data, we calculated mean differences (MD), again based on a random-effects model. We assessed risk of bias for each included study. MAIN RESULTS: We included 12 trials involving 6389 patients. Aripiprazole was compared to olanzapine, risperidone and ziprasidone. All trials were sponsored by an interested drug manufacturer. The overall number of participants leaving studies early was 30% to 40%, limiting validity (no differences between groups).When compared with olanzapine no differences were apparent for global state (no clinically important change: n = 703, 1 RCT, RR short-term 1.00 95% CI 0.81 to 1.22; n = 317, 1 RCT, RR medium-term 1.08 95% CI 0.95 to 1.22) but mental state tended to favour olanzapine (n = 1360, 3 RCTs, MD total Positive and Negative Syndrome Scale (PANSS) 4.68 95% CI 2.21 to 7.16). There was no significant difference in extrapyramidal symptoms (n = 529, 2 RCTs, RR 0.99 95% CI 0.62 to 1.59) but fewer in the aripiprazole group had increased cholesterol levels (n = 223, 1 RCT, RR 0.32 95% CI 0.19 to 0.54) or weight gain of 7% or more of total body weight (n = 1095, 3 RCTs, RR 0.39 95% CI 0.28 to 0.54).When compared with risperidone, aripiprazole showed no advantage in terms of global state (n = 384, 2 RCTs, RR no important improvement 1.14 95% CI 0.81 to 1.60) or mental state (n = 372, 2 RCTs, MD total PANSS 1.50 95% CI -2.96 to 5.96).One study compared aripiprazole with ziprasidone (n = 247) and both the groups reported similar change in the global state (n = 247, 1 RCT, MD average change in Clinical Global Impression-Severity (CGI-S) score -0.03 95% CI -0.28 to 0.22) and mental state (n = 247, 1 RCT, MD change PANSS -3.00 95% CI -7.29 to 1.29).When compared with any one of several new generation antipsychotic drugs the aripiprazole group showed improvement in global state in energy (n = 523, 1 RCT, RR 0.69 95% CI 0.56 to 0.84), mood (n = 523, 1 RCT, RR 0.77 95% CI 0.65 to 0.92), negative symptoms (n = 523, 1 RCT, RR 0.82 95% CI 0.68 to 0.99), somnolence (n = 523, 1 RCT, RR 0.80 95% CI 0.69 to 0.93) and weight gain (n = 523, 1 RCT, RR 0.84 95% CI 0.76 to 0.94). Significantly more people given aripiprazole reported symptoms of nausea (n = 2881, 3 RCTs, RR 3.13 95% CI 2.12 to 4.61) but weight gain (7% or more of total body weight) was less common in people allocated aripiprazole (n = 330, 1 RCT, RR 0.35 95% CI 0.19 to 0.64). Aripiprazole may have value in aggression but data are limited. This will be the focus of another review. AUTHORS' CONCLUSIONS: Information on all comparisons are of limited quality, are incomplete and problematic to apply clinically. Aripiprazole is an antipsychotic drug with a variant but not absent adverse effect profile. Long-term data are sparse and there is considerable scope for another update of this review as new data emerges from the many Chinese studies as well as from ongoing larger, independent pragmatic trials