Gas concentration pre-warning system based on fuzzy structured element

In order to accurately test gas concentration and effectively pre-warning when the gas concentration over-limited on work face,used the high-performance and low prices SCM and the low-cost and high transfer efficiency bluetooth technology to forecast the gas concentration in real time.The data tested by SCM,then got the corresponding mathematical model of the data.Put forward the idea of using fuzzy structured element theory to dynamic forecast the gas concentration,analyzed the features in abnor- mal-effusing on work face and judge whether there was the possibility of abnormal gas-effusion.Simulation results show that mathematical model of this system about gas concentration is correct.This system changes coal mine monitoring system's traditional way of after-alarming into early-warning,and thus enhances its feasibility.

Effect of chloride ion on bacterial pre-oxidation of arsenic-containing gold concentrate

The bacterial pre-oxidation process of arsenic-containing gold concentrates and the bacterial activity under different chloride ion concentrations were studied by using a mixture of thermophilic strains TCJ domesticated in production.The experimental result shows that with different samples and leaching systems,the adaptability and Cl- tolerance of bacteria are different,and that appropriate chloride ion concentration is conductive to bacterial oxidation,while higher chloride ion concentration will inhibit the bacterial activity and affect the pre-oxidation performance.Under the present production conditions,TCJ can adapt to the changes of water quality in the source of water and its critical chloride ion tolerance value is 2.7 g/L.

Study on Antibacterial Activity of 2-Methyl-3-(methylthio)Pyrazine Against Three Strains of Spoilage Bacteria

Previous studies have shown that glycine and proline are pharmacophores that display antibacterial activity.In the present study,glycine and proline were derivated to diketopiperazine compounds by chemical synthesis method,and their antibacterial activities were evaluated by three strains of spoilage bacteria,Escherichia coli,Pseudomonas aeruginosa and Shewanella putrefaciens,and the relationship of their antibacterial activities and structures was also investigated.Uv-vis spectrophotometry was used to determine the growth curves of three kinds of active indicator bacteria.Minimum inhibitory concentration(MIC)was determined by micro broth dilution method.The results showed that 2-methyl-3-(methylthio)pyrazine had significant antibacterial activity against three strains of the bacteria,and its MIC was 1.25%.It indicates 2-methyl-3-(methylthio)pyrazine has the potential to be developed as a kind of preservative in future.

CRITICAL CONCENTRATIONS OF α(1→3)-D-GLUCAN FROM LENTINUS EDODES IN NaOH AQUEOUS SOLUTION

Critical concentrations of α-(1→3)-D-glucan L-FV-Ⅱ from Lentinus edodes were studied by viscometry andfluorescence probe techniques. The dependence of the reduced viscosity on concentration of the glucan in 0.5 mol/L NaOHaqueous solutions with or without urea showed two turning points corresponding to the dynamic contact concentration c_s andthe overlap concentration c~* of the polymer. The values of c_s and c~* were found to be 1×10^(-3) g cm^(-3) and 1.1×10^(-2) g cm^(-3),respectively, for L-FV-Ⅱ in 0.5 mol/L NaOH aqueous solutions. The two critical concentrations of L-FV-Ⅱ in 0.5 mol/LNaOH aqueous solutions were also found to be 1.2×10^(-3) g cm^(-3) fbr c_s and 9.2×10^(-3) g cm^(-3) for c~* from the concentrationdependence of phenanthrene fluorescence intensities. The overlap concentration c~* of L-FV-Ⅱ in 0.5 mol/L NaOH aqueoussolutions was lower than that of polystyrene with same molecular weight in benzene, owing to the fact that polysaccharidetends to undergo aggregation caused by intermolecular hydrogen bonding. A normal viscosity behavior of L-FV-Ⅱ in 0.5 mol/L urea/0.5 mol/L NaOH aqueous solutions can still be observed in an extremely low concentration range at 25℃.

HBV PreS2+S/IFN-α融合基因真核表达载体的构建及其表达

构建含HBVPrdS2 +S和IFN α融合基因的真核表达载体pcDNA3.1.S2S/IFN α并在真核细胞中进行表达。应用重叠延伸剪切技术 (splicingbyoverlappingextension ,简称SOE)经两次PCR获得嵌合基因片段S2S/IFN α ,回收后直接克隆到 pcDNA3.1V5 /HisTOPOTA克隆载体 ,得到真核重组载体pcDNA3.1.S2S/IFN α。然后用脂质体法转染VeroE6细胞。对重组载体进行了限制性酶切及PCR鉴定 ,证明连接正确 ;经间接免疫荧光检测证实该重组载体能在真核细胞中表达插入的外源性基因编码的融合蛋白。真核表达载体pcDNA3.1.S2S/IFN α的成功构建及在VeroE6细胞中的有效表达 。

某金精矿焙烧氧化-氰化浸金试验研究

对甘肃某复杂难处理金精矿进行焙烧氧化-氰化浸金试验研究。通过条件优化试验,确定最佳氧化焙烧工艺参数。在金精矿磨矿细度-0.074 mm占79.24%,一段焙烧温度为550℃、充气含氧量为10%、焙烧时间为1.0 h,二段焙烧温度为650℃、充气含氧量为21%、焙烧时间为1.0 h的条件下,焙砂中砷、碳和硫的脱除率分别为89.22%、72.05%和95.51%,金浸出率为83.76%。

Preβ-1高密度脂蛋白与心血管疾病关系的研究进展

动脉粥样硬化是心血管疾病重要的病理生理基础,延缓和防治动脉粥样硬化对于减少和降低心血管疾病的发病率及病死率具有重要意义。高密度脂蛋白(high density lipoprotein,HDL)通过参与介导胆固醇逆向转运(reverse cholesterol transport,RCT)在抗动脉粥样硬化的形成和进展中发挥了重要作用。Preβ-1高密度脂蛋白(prebeta-1 high density lipoprotein,Preβ-1HDL)作为HDL的一种亚类,是外周细胞移出胆固醇的最初接受体,直接参与了RCT的起始步骤,并在随后的胆固醇酯化及转运中起着重要作用。本文就Preβ-1HDL的结构、代谢及其与心血管疾病的关系作一简要综述。

Study on Preparation and Electrical Properties of Ba_(1.03)Ce_(0.8)Eu_(0.2)O_(3-α) Solid Electrolyte

Ba_(1.03)Ce_(0.8)Eu_(0.2)O_(3-α) solid electrolyte with nonstoichiometric composition was prepared by high temperature solid-state reaction. Phase composition, surface and fracture morphologies of the specimen were characterized by using XRD and SEM, respectively. Ionic conduction was researched by gas concentration cell, the performance of hydrogen-air fuel cell was measured in the temperature range of 600～1000 ℃, and compared them with those of BaCe_(0.8)Eu_(0.2)O_(3-α) and Ba_(0.98)Ce_(0.8)Eu_(0.2)O_(3-α). The results indicate that Ba_(1.03)Ce_(0.8)Eu_(0.2)O_(3-α) is a single-phase perovskite-type orthorhombic system. It is a pure proton conductor in the temperature range of 600～1000 ℃ in hydrogen atmosphere, and its proton conduction is superior to that of BaCe_(0.8)Eu_(0.2)O_(3-α) and Ba_(0.98)Ce_(0.8)Eu_(0.2)O_(3-α). It is a mixed conductor of oxide ion and electron hole in oxygen atmosphere. At 1000 ℃, the performance of the fuel cell in which Ba_(1.03)Ce_(0.8)Eu_(0.2)O_(3-α) as electrolyte is higher than that of BaCe_(0.8)Eu_(0.2)O_(3-α) or Ba_(0.98)Ce_(0.8)Eu_(0.2)O_(3-α).

某难选弱磁性铁矿磁化焙烧-磁选试验研究

对江苏某难选弱磁性铁矿石进行了预还原磁化焙烧-磁选试验研究。结果表明,矿样在预还原反应温度750℃、反应时间60 min、还原剂煤用量3%、磨矿细度-0.074 mm粒级占75%条件下,经一粗一精一扫弱磁选,可获得铁品位65.05%、铁回收率96.19%的高品质铁精矿。研究结果可为难选弱磁性铁矿石选别提供一定参考。

预浓缩-GC-MS/FID测定环境空气中116种挥发性有机物

采用预浓缩-气相色谱-质谱/氢火焰离子化检测器联用法(预浓缩-GC-MS/FID)结合Dean Switch中心切割和冷柱箱技术,建立了测定环境空气中116种挥发性有机物(VOCs)的分析方法。通过分析色谱程序升温、预浓缩系统一级冷阱、二级冷阱等条件对测定结果的影响,确定了最优参数,评估了此条件下的方法稳定性和准确性。结果显示,程序升温为-20℃~240℃、一级冷阱解析温度为5℃及二级冷阱捕集温度为-50℃时测定效果最佳,116种VOCs在0.50~20.0 nmol·mol^(-1)范围内线性良好,相关系数(R^(2))为0.994~0.9999;在5.00 nmol·mol^(-1)加标浓度水平下重复进样6次,加标回收率为91.2%~117%,相对标准偏差(RSD)为2.3%~12%。方法简便快速、稳定性好、准确度高,可用于环境空气中116种VOCs的定性定量分析。

预造球强化难制粒精矿烧结工艺

随着进口铁矿石价格的增长,充分利用廉价的难处理铁矿资源成为钢铁企业降本增效的关键。本文针对难制粒精矿在烧结中利用率低的问题,在复合造块法的基础上开发了预造球工艺,显著提高了难制粒精矿的配入量,有效改善了制粒效果与烧结产、质量指标。研究表明,在难制粒精矿配比达到36%时,采用预造球制粒可以使准颗粒平均粒径提高1.53 mm,透气性指数提高0.17。在此基础上,垂直烧结速度提高13.97 mm/min,利用系数提高0.815 t/(m^(2)·h),转鼓强度提高3.39%。预造球烧结中,由于难制粒精矿的分离,常规制粒料部分的制粒性能得到优化,局部碱度得到提高,形成大量的针柱状铁酸钙。在常规制粒料与球团料交界处固相固结与液相固结同时存在,铁酸钙与铁氧化物相互交织,形成球团嵌入式分布的成品矿结构,具有良好的成矿效果和强度性能。

采用自主研发的在线前处理系统同时分析脱硫废水中阴阳离子

电厂专用的全自动脱硫废水分析仪可以实现对超高浓度脱硫废水的自动化前处理以及分析,样品通过自动二步稀释,并与双系统离子色谱仪联用,对脱硫废水中的阴、阳离子同时进行检测。脱硫废水中阳离子主要有Na+、NH4+、K+、Mg2+、Ca2+,阴离子主要有F-、Cl-、NO3-、SO42-。本研究对仪器相关参数进行了验证,测试结果为,4种阴离子和5种阳离子的混合标准溶液在其线性关系内相关系数均大于0.999;4种阴离子的峰高和峰面积重复性RSD小于2.29%,5种阳离子的峰高和峰面积重复性RSD小于1.78%,实际样品中4种加标阴离子回收率在93.5%~100.2%之间;5种阳离子加标回收率在95.4%~103.8%之间。结果证明,该系统大大提高了分析效率,节省了人工成本,填补了市场空白。

活性炭吸附分离-分光光度法测定硫化矿和土壤中的痕量铊

详细研究并确定了在HCl介质中 ,活性炭吸附Tl及草酸铵解吸Tl的诸条件 ,使Tl与干扰元素分离而预富集 ,回收率在 99.6 %～ 1 1 6 .3 %。以镉试剂 2B为显色剂 ,准确测定了硫化矿和土壤中的Tl。考察了两个样品测定 5次的相对标准偏差 <6 % ,试样分析结果与原子吸收法、等离子体质谱法及泡沫塑料吸附分离 -镉试剂 2B光度法结果基本一致。

高效液相色谱-离子阱质谱法测定人血浆中的头孢拉定和青霉素G

目前,β-内酰胺类抗生素在临床抗感染药物中占有十分突出的地位[1],但在近年来的药品不良反应报告中,抗生素类药物引起的不良反应也占据了很高的比例,其中有我国生活环境影响、感染性疾病多的客观因素,但病人用药盲目性大、医生用药随意性多的问题也普遍存在.……

丹宁棉分离富集-发射光谱法同时测定地质样品中微量铌钽锆铪

采用丹宁棉对地质样品溶液中的铌、钽、锆、铪进行分离富集 ,将富集后的丹宁棉在60 0℃灼烧 30min ,灰分用发射光谱法同时测定四元素。检出限与通常的发射光谱法相比降低约2个数量级 ,经国家级标准物质检验 ,结果与标准值相符。精密度试验 ,各元素的RSD(n =2 0 )为 2 .6%～ 7.9%。

弱碱性阴离子树脂分离富集-发射光谱法测定痕量钯

在盐酸介质中，钯与氯离子发生反应生成配合物[PdCl6]^2-，该配合物能被大孔弱碱性苯乙烯系阴离子交换树脂吸附。吸附物灰化后，灰分与缓冲剂混合均匀，全部装入杯形电极，发射光谱法测定钯。方法检出限为0．12ng／g（10．0g样品）。方法经国家一级标准物质验证，测定值与标准值相符，精密度（RSD，n=12）为8．9％～13．9％，回收率为89％～118％。方法已用于测定水系沉积物中的痕量钯。

预浓缩-气质联用法测定高山大气中氯氟烃

建立了预浓缩-气相色谱/质谱联用技术,同时检测高山大气中二氟二氯甲烷、四氟二氯乙烷、一氟三氯甲烷、三氟三氯乙烷的分析方法。4种物质的检出限分别为0.013、0.022、0.021、0.030μg/m^3,相对标准偏差在5.6%以下,标准曲线相关系数大于0.996,加标回收率为93.2%~98.3%。对庐山大气进行监测,结果表明,庐山大气中4种氯氟烃的浓度均高于武夷山和湖北神龙架大气背景点,庐山大气中CFC-11、CFC-113的浓度接近于泰山和贡嘎山的浓度。

血清中美西律的柱前衍生化-液相色谱荧光检测

目的 建立血清中盐酸美西律的柱前衍生化 液相色谱荧光检测法。方法 血清样品用丙酮液直接沉淀蛋白后 ,定量加入荧光胺丙酮溶液 ,得盐酸美西律的荧光衍生物。采用AlltimaC1 8(15 0mm× 4 6mm ,5 μm)为分析柱 ;流动相为甲醇 水 2 4mol·L- 1 二乙胺 磷酸缓冲液 (pH 4 0 ) (70∶2 8∶2 ) ;荧光检测激发波长 (Ex)为 392nm ,发射波长(Em)为 4 80nm。盐酸美西律的保留时间为 6 5min。结果 盐酸美西律在 0 10 0～ 6 4 0 0mg·L- 1 线性关系良好。本法的最低检测质量浓度为 5 μg·L- 1 ,(S N≥ 4 )。批内、批间精密度为 1 34%～ 5 31%。结论 本法操作简便、有良好的灵敏度和专一性 。

石煤提钒预富集分离过程中的松散-分层模型(英文)

在扫描电镜矿物定量评价(QEMSCAN)工艺矿物学研究的基础上,采用摇床分选工艺对石煤中的钒进行预富集,以实现提高钒品位的同时,降低耗酸矿物的含量;并利用Bagnold剪切理论和Kelly分层假说建立分离过程中的松散-分层模型,以阐述含钒基体矿物从分选体系中分离的机理,且对模型进行验证。模型结果表明,细粒级含钒基体矿物和粗粒级含钒基体矿物分别在粗选和扫选阶段实现分离;在模型计算过程中确定了影响粗选和扫选阶段分离的主导因素,分别为重力沉降和摇床床面的不对称往复运动产生的剪切分散压。