甘肃某细粒浸染型金矿石选矿试验研究

甘肃某细粒浸染型金矿石中金主要以包裹金形态存在,且载金矿物黄铁矿与脉石矿物连生关系复杂。针对该矿石的性质,进行了选矿试验研究。其结果表明:在最佳试验条件下,采用阶段磨矿-阶段浮选工艺,可获得金品位30.17 g/t、金回收率81.23%的较好指标;硫精矿经氧化焙烧—氰化浸出,金对原矿的回收率为6.96%,金总回收率达88.19%。

华北某细粒闪石型贫磁铁矿石全弱磁选流程研究与工业实践

华北某细粒闪石型贫磁铁矿石嵌布粒度极细,嵌布关系复杂,铁硅酸盐含量高,弱磁性铁矿物回收难度大,且回收成本较高,能否实现粗粒预选、阶磨阶选、高效精选是该矿石经济高效开发的关键。项目着重进行了预选研究,并在常规的阶段磨矿-阶段弱磁选基础上,对弱磁精矿进行了淘洗精选试验,为大规模工业化低成本开发提供了可供借鉴的参考经验。

具有缓释作用的新剂型——氟乐灵24%细粒除草剂

氟乐灵(trifluralin)是美国陶氏益农公司开发的苯胺类、内吸传导型选择性除草剂,旱地、水田兼用。我省东阳农药厂也已研制投产,目前应市的主要是48％乳油。氟乐灵是历史悠久的长寿品种,因适合多种农作物防除多种禾本科及部分阔叶草,而深受用户欢迎。但其同时又具有易挥发、光解而影响防除效果的缺陷,所以,虽然国外近年来旱地除草剂销售量增长幅度很快,但氟乐灵的市场占有率及应用面积却一直徘徊不前。

SPM2025型双向细粒破碎机选型设计

细碎机是火电厂输煤系统中重要的辅机设备,主要用于细碎电站用煤,亦可破碎属理、节理、裂纹较发育等脆性物料,尤其适合循环硫化床锅炉用料的细粒破碎。本文重点对SPM2025型双向细粒破碎机进行理论研究,进行参数选取及出力计算、启动功率计算、盘车机构设计计算等。

岩相、生物相、古地理与微细粒金矿矿源层

本文以黔西南二叠——三叠系为例,探讨微细粒浸染型金矿矿源层与古地理、岩相、岩性、化石群落的关务,认为盆地边缘相、台盆相的含金量高于其它相。金往往在泥岩、粘土岩和富含软体动物的层位中富集。

基于深度学习的细骨料图像实时分割提取

文章基于深度学习算法对细骨料投影图像进行分割,通过对比传统阈值分割与PSPNet、DeepLab V3+、U-Net深度学习网络模型算法的分割结果对4种模型进行评价分析,同时实验对比细骨料2种等效粒径计算方法(单面投影法、双面投影法)的粒径和级配分布结果。结果表明:深度学习模型算法中U-Net网络模型的准确率、召回率、F平衡分数和交并比分别达到99.8%、88.1%、84.9%、84.3%,均优于对比组模型;对于3种不同粒径的单粒段细骨料,采用双面投影法计算出的细骨料等效粒径D d与实际细骨料粒径的偏差分别为1.40%、2.10%、3.12%;对于混合粒段骨料,采用等效粒径D d计算出的级配分布曲线更接近筛分法的实验结果,具有普遍适用性。研究结果可为细骨料径粒径和粒型参数的计算提取提供新的思路。

南岭苗儿山地区沙坪岩体型白钨矿床地质特征及找矿意义

沙坪岩体型白钨矿床位于南岭成矿带西段苗儿山岩体北西部,是近年来新发现的矿床。矿体由苗儿山岩体北段志留纪第六次侵入细粒含电气石二长花岗岩小岩株发生全岩矿化所形成;矿床地质特征及岩矿鉴定资料显示矿石无明显的热液蚀变的特征,推断矿床类型为细粒花岗岩型白钨矿床,成矿年龄与岩石成岩年龄一致,为加里东期;该矿床的发现表明南岭地区不仅只是经历了燕山期大规模岩浆成矿事件,也经历了加里东期成岩成矿事件;在地质找矿工作相对薄弱的南岭成矿带西段广泛发育加里东期花岗岩,今后应注意该地区同类型矿床的找矿工作。

Identification of Macropterous Individual of Cixiopsis punctatus(Hemiptera:Fulgoroidea:Tropiduchidae) Based on Morphological and Molecular Data

The macropterous individual of Cixiopsis punctatus Matsumura is recognized based on morphological comparison and the mitochondrial COI gene sequences.The pairwise distances among the specimens examined ranged from 0 to 0.0228.Mean distance between macropterous female（Cixiopsis sp.） and 5 brachypterous specimens of Cixiopsis punctatus is 0.0161,which was close enough to consider the macropterous female and brachypterous specimens to be the same species.The external morphology of macropterous female of Cixiopsis punctatus is firstly illustrated and described.

Fine-Grain Sleep Transistor Insertion for Leakage Reduction

A fine-grain sleep transistor insertion technique based on our simplified leakage current and delay models is proposed to reduce leakage current. The key idea is to model the leakage current reduction problem as a mixed-integer linear programming （MLP） problem in order to simultaneously place and size the sleep transistors optimally. Because of better circuit slack utilization, our experimental results show that the MLP model can save leakage by 79.75%, 93.56%, and 94.99% when the circuit slowdown is 0%, 3%, and 5%, respectively. The MLP model also achieves on average 74.79% less area penalty compared to the conventional fixed slowdown method when the circuit slowdown is 7%.

Coimmunization with IL-15 plasmid enhances the longevity of CD8 T cells induced by DNA encoding hepatitis B virus core antigen

AIM： To test the feasibility of delivering a plasmid encoding IL-15 as a DNA vaccine adjuvant for improving the immune responses induced by hepatitis B virus core gene DNA vaccine. METHODS： We used RT-PCR based strategies to develop IL-15 expression constructs. We first confirmed that the gene could be expressed in Escherichia coli due to the poor expression of IL-15. Then the bioactivity of IL-15 plasmid expression product was identified by CTLL-2 proliferation assay. One hundred micrograms of DNA from each of the IL-15 eukaryotic expressed plasmid and the recombinant plasmid harboring DNA encoding the 144 amino acids of the N-terminus of HBV core gene （abbreviated pHBc144） was used to co-immunize C57 BL/6 mice. The titer of anti-HBcIgG was detected by ELISA and the antigen-specific CD8^＋T cells （CD8^＋IFN-γ^＋ T cells） were detected by intracellular cytokine staining at different time points. RESULTS： After co-immunization by pIL-15 and pHBc144 DNA vaccine the antigen-specific CD8^＋ cells of mice increased gradually, the first peak of immune response appeared 14 d later, then the number of antigen-specific CD8^＋Ts cells decreased gradually and maintained at a steady level in 3 mo. After boosting, the number of antigen-specific CD8^＋T cells reached the second peak 10 d later with a double of the 1st peak, then the number of antigen-specific CD8^＋T cells decreased slowly. IL-15 as a gene adjuvant had no significant effect on humoral immune responses induced by hepatitis B virus core gene DNA vaccine, but increased the memory antigen-specific CD8^＋T cells induced by hepatitis B virus core gene DNA vaccine. CONCLUSION： DNA vaccine constructed by HBc Ag 1-144 amino acid induces effective cell immunity, and cytokine plasmid-delivered IL-15 enhances the longevity of CD8^＋ T cells.

甘肃某金矿阶段磨浮工艺提高金回收指标试验

甘肃某金矿选矿厂采用一段磨浮工艺回收细粒浸染型难选金矿石中的金,金回收率仅在78%左右。为提高金回收率,在探索试验基础上进行了阶段磨浮工艺研究。试验研究表明,采用阶段磨浮工艺流程处理金品位为2.86 g/t的矿石,在一段磨矿细度为-0.074 mm52%、二段磨矿细度为-0.074 mm87%、用氧化钙调矿浆pH值=8.0、丁基黄药用量为150 g/t、2#油用量为95 g/t情况下,闭路试验获得的综合精矿金品位为41.77 g/t、回收率为86.51%,金回收率提高约8个百分点,经济效益显著。

A case of steroid-dependent myeloid granulocytic sarcoma masquerading as Crohn's disease

Small bowel tumors and Crohn's disease are common causes of small bowel obstruction.Early stage neoplasms can easily be mistaken for Crohn's disease.Therefore,thorough work-ups including imaging studies and endoscopic evaluation with biopsies are critical for accurate diagnosis.Here we report a case of an otherwise healthy female with progressive onset of multiple,recurrent obstructive symptoms secondary to terminal ileal narrowing who was referred for management of steroid-dependent Crohn's disease.After thorough evaluation,the diagnosis was revised to myeloid granulocytic sarcoma involving the terminal ileum.In this case,a delay in diagnosis can be detrimental for prognosis,as myeloid granulocytic sarcoma is highly predictive of underlying acute myeloid leukemia and needs urgent referral for chemotherapy and/or resection.

Edaravone protects PC12 cells from ischemic-like injury via attenuating the damage to mitochondria

Background： Edaravone had been validated to effectively protect against ischemic injuries. In this study, we investigated the protective effect of edaravone by observing the effects on anti-apoptosis, regulation of Bcl-2/Bax protein expression and recovering from damage to mitochondria after OGD （oxygen-glucose deprivation）-reperfusion. Methods： Viability of PC 12 cells which were injured at different time of OGD injury, was quantified by measuring MTT （2-（4,5-dimethylthia-zol-2-yl）-2,5-diphenyltetrazolium bromide） staining. In addition, PC 12 cells＇ viability was also quantified after their preincubation in different concentration of edaravone for 30 min followed by （OGD）. Furthermore, apoptotic population of PC 12 cells that reinsulted from OGD-reperfusion with or without preincubation with edaravone was determined by flow cytometer analysis, electron microscope and Hoechst/Pl staining. Finally, change of Bcl-2/Bax protein expression was detected by Western blot. Results： （1） The viability of PC12 cells decreased with time （1-12 h） after OGD. We regarded the model of OGD 2 h, then replacing DMEM （Dulbecco＇s Modified Eagle＇s Medium） for another 24 h as an OGD-reperfusion in this research. Furthermore, most PC 12 cells were in the state of apoptosis after OGD-reperfusion. （2） The viability of PC 12 cells preincubated with edaravone at high concentrations （1, 0.1, 0.01 μmol/L） increased significantly with edaravone protecting PC 12 cells from apoptosis after OGD-reperfusion injury. （3） Furthermore, edaravone attenuates the damage of OGD-reperfusion on mitochondria and regulated Bcl-2/Bax protein imbalance expression after OGD-reperfusion. Conclusion： Neuroprotective effects of edaravone on ischemic or other brain injuries may be partly mediated through inhibition of Bcl-2/Bax apoptotic pathways by recovering from the damage of mitochondria.

ONCOGENIC TRANSFORMATION OF SYRIAN HAMSTER EMBRYO CELLS BY 5．3－MeV α PARTICLES AND A TUMOR PROMOTER PHORBOL ESTER

The primary Syrian hamster embryo(SHE) cells were used to study the oncogenic transformation by ￣(238)pu α particles or X-rays alone or in combination with a chemical promoter phorbol ester.Survival curves of SHE cells following exposure to α-particles or X-rays were fitted to single-or multi-target models,respectively. Model parameters were: Do = 0. 55 Gy. n = 1 for α particles 4 Do = 1.44 Gy. Dq = 3.0 Gy. n=7.7 for X-rays.Incidence of α particles or X-rays induced cell transformation was dose-dependant.α particles were more efficient in inducing cell transformation than that of X-rays. The enhancement of SHE cell transformation by phorbol 12-myristate 13-acetate(PMA) following exposure to α particles of 0. 25-1. 00 Gy was observed.

Modeling of fine coal flotation separation based on particle characteristics and hydrodynamic conditions

Flotation is a complex multifaceted process that is widely used for the separation of finely ground minerals. The theory of froth flotation is complex and is not completely understood. This fact has been brought many monitoring challenges in a coal processing plant. To solve those challenges, it is important to understand the effect of different parameters on the fine particle separation, and control flotation performance for a particular system. This study is going to indicate the effect of various parameters （particle Characteristics and hydrodynamic conditions） on coal flotation responses （flotation rate constant and recovery） by different modeling techniques. A comprehensive coal flotation database was prepared for the statistical and soft computing methods. Statistical factors were used for variable selections. Results were in a good agreement with recent theoretical flotation investigations. Computational models accurately can estimate flotation rate constant and coal recovery （correlation coefficient 0.85, and 0.99, respectively）. According to the results, it can be concluded that the soft computing models can overcome the complexity of process and be used as an expert system to control, and optimize parameters of coal flotation process.

Crystallographic study of Al_3Zr and Al_3Nb as grain refiners for Al alloys

The potency of Al3Zr and Al3Nb as grain refiners for Al alloys was investigated from a crystallographic point of view using the edge-to-edge matching （E2EM） model. The results show that both Al3Zr and Al3Nb have small values of interatomic spacing misfit and interplanar spacing mismatch with respect to Al. Furthermore, energetically favourable orientation relationships predicted by the model exist between Al and each of these two intermetallic phases. In the light of the edge-to-edge matching model predictions, it is suggested that both Al3Zr and Al3Nb are potent heterogeneous nucleation refiners for Al grains from the crystallographic point of view. The present crystallographic analysis provides a more reasonable explanation for the significant grain refinement obtained in the peritectic Al-Zr and Al-Nb alloys and also provides fresh insight into the understanding of the grain refinement mechanism of Al alloys.

栾川老庙沟钼矿试验研究

栾川该钼矿主要有价成分为钼,Cu、Pb、Zn含量甚低。选矿试验的目的是,通过试验研究探索该矿是否可通过药剂制度的优化调整,达到提高钼矿选矿指标的可能性,探索试验内容包括:磨矿细度条件试验;钼硫混浮调整剂、捕收剂种类及用量试验;钼硫分离药剂种类及用量探索试验;优先浮钼—尾矿钼硫混浮—钼硫分离条件试验,主要探索试验内容及结果如下。

HIV-1 Vpr-induced cell death in Schizosaccharomyces pombe is reminiscent of apoptosis

Human immunodeficiency virus type 1 （HIV-1） Vpr induces cell death in mammalian and fssion yeast cells, suggesting that Vpr may affect a conserved cellular process. It is unclear, however, whether Vpr-induced yeast cell death mimics Vpr-mediated apoptosis in mammalian cells. We have recently identified a number of Vpr suppressors that not only suppress Vpr-induced cell death in fission yeast, but also block Vpr-induced apoptosis in mammalian cells. These findings suggest that Vpr-induced cell death in yeast may resemble some of the apoptotic processes of mammalian cells. The goal of this study was to develop and validate a fission yeast model system for future studies of apoptosis. Similar to Vpr-induced apoptosis in mammalian cells, we show here that Vpr in fission yeast promotes phosphatidylserine externalization and induces hyperpolarization of mitochondria, leading to changes of mitochondrial membrane potential. Moreover, Vpr triggers production of reactive oxygen species （ROS）, indicating that the apoptotic-like cell death might be mediated by ROS. Interestingly, Vpr induces unique morphologic changes in mitochondria that may provide a simple marker for measuring the apoptotic-like process in fission yeast. To verify this possibility, we tested two Vpr suppressors （EF2 and Hspl6） that suppress Vpr-induced apoptosis in mammalian cells in addition to a newly identified Vpr suppressor （Skpl）. All three proteins abolished cell death mediated by Vpr and restored normal mitochondrial morphology in the yeast cells. In conclusion, Vpr-induced cell death in fission yeast resembles the mammalian apoptotic process. Fission yeast may thus potentially be used as a simple model organism for the future study of the apoptotic-like process induced by Vpr and other proapoptotic agents.

Properties and interfacial microstructure of cement-based materials with composite micro-grains

Silica fume, fly ash and nano-fiber mineral materials (NR powder) are employed to incorporate into cement-based materials. According to the grain grading mathematical model of cement-based materials, two packing systems, namely, spherical grading system and nano-fiber reinforced system were designed. Properties and interfacial microstructure of the two systems were studied according to secondary interface theory. It was shown that nano-fiber mineral materials can improve the grain grading of the admixture, increase the density of the system, improve the microstructure of the interface and the hardened paste, and enhance the uniformity of cement-based materials mixed with composite micro-grains and greatly increase their wearable rigidity and flexure strength. In this paper, two kinds of interface models, including spherical grain model and nano-fiber reinforced interface model of the cement-based materials mixed with composite micro-grains, were brought forward.

Three Times Spontaneous Remission of Severe Aplastic Anemia Following Granulocyte Transfusion from Related Donors:a Case Report and Literature Review

APLASTIC anemia （AA） is a bone marrow failure disease caused by abnormal activation of T lymphocytes, resulting in the apoptosis of he- matopoietic cells and bone marrow failure.