SO2-4/Fe2O3固体超强酸催化合成乙酸丁酯

制备固体超强酸SO4 2 - /Fe2 O3,并测定其红外光谱。以乙酸和正丁醇为反应物、固体超强酸SO4 2 - /Fe2 O3为催化剂 ,进行合成乙酸丁酯的研究。实验结果表明 ,固体超强酸SO4 2 - /Fe2 O3在合成乙酸丁酯反应中的催化活性与浓硫酸相当 ,用 0 1mol正丁醇与 0 2mol乙酸反应 ,催化剂用量 0 3g ,回流时间 90min ,乙酸丁酯收率为 63 8%。     

SO4^2—／Fe2O3固体超强酸化催合成乙酸丁酯

制备固体超强酸SO4^2-/Fe2O3，并测定其红外光谱。以乙酸和正丁醇为反应物、固体超强酸SO4^2-/Fe2O3为催化剂，进行合成乙酸丁酯的研究。实验结果表明，固体超强酸SO4^2-/Fe2O3在合成乙酸丁酯反应中的催化活性与浓硫酸相当，用0．1mol正丁醇与0．2mol乙酸反应，催化剂用量0．3g，回流时间90min，乙酸丁酯收率为63．8％。     

4种重金属离子及其混合液对壶状臂尾轮虫的急性毒性试验

研究了铜、锌、镉、铅离子及其混合液对壶状臂尾轮虫(Brachionusurceus)的急性毒性影响,实验结果表明,Cu2+、Zn2+、Cd2+、Pb2+对壶状臂尾轮虫的24hLC50分别为83 .18μg/L、4 .27mg/L、7. 60mg/L、23 44mg/L,将4种离子按照质量比120∶20∶6∶1的比例配成混合金属溶液,其混合液对壶状臂尾轮虫的24hLC50为0 42mg/L。     

改进重铬酸钾法快速测定水样CODcr

研究了用硫酸锰代替贵金属硫酸银作催化剂,在H2SO4-H3PO4介质中,重铬酸钾回流法测定水样中CODcr的新方法.通过实验,确定了最佳测定条件:MnSO4浓度为1×10-1mol.L-1;混酸溶液(H2SO4:H3PO4)=5:1(体积比);回流时间10min.并与标准方法进行了对比,准确度和精密度同标准法相近,大大节约了分析时间.     

Predicting size effect on diffusion-limited current density of oxygen reduction by copper wire

The size effect of copper wire radius (0.04–0.82 mm) on the diffusion-limited current density of an oxygen reduction reaction in stagnant simulated seawater (naturally aerated 0.5 mol/L NaCl) is investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) and compared with the results obtained in 0.5 mol/L H2SO4. In the oxygen diffusion-limited range, size effect is found to occur independent of electrolytes, which is attributed to non-linear diffusion. Additionally, to sati...     

Predicting size effect on diffusion-limited current density of oxygen reduction by copper wire

The size effect of copper wire radius (0.04–0.82 mm) on the diffusion-limited current density of an oxygen reduction reaction in stagnant simulated seawater (naturally aerated 0.5 mol/L NaCl) is investigated by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) and compared with the results obtained in 0.5 mol/L H2SO4. In the oxygen diffusion-limited range, size effect is found to occur independent of electrolytes, which is attributed to non-linear diffusion. Additionally, to satisfy application in a marine setting, an empirical equation correlating oxygen diffusion-limited current density to copper wire radius is proposed by fitting experimental data.     

方斑东风螺对饲料中铜的需要量

以硫酸铜为铜源,在基础饲料中分别添加0、1、3、5、8、12和20 mg/kg的铜,配制出铜质量分数为1.2、2.1、3.9、6.2、9.0、13.4、20.5 mg/kg的7种实验饲料,投喂方斑东风螺(Babylonia areolata)8周,研究方斑东风螺对铜的需要量(养殖水体中铜质量浓度为2.91μg/L)。结果表明:饲料铜含量对方斑东风螺生长性能、饲料系数(FCR)和蛋白质效率(PER)影响无统计学意义(P0.05);螺软体部总超氧化物歧化酶(SOD)、铜锌超氧化物歧化酶(Cu-ZnSOD)、过氧化氢酶(CAT)和铜ATP转运酶(Cu-ATPase)活力随着饲料铜水平的增加而增加,分别在饲料铜水平为6.2、3.9、6.2和6.2 mg/kg达到最大值;饲料铜质量分数超过9.0 mg/kg时,螺软体部铜含量随着饲料铜水平的增加而增加,差异有统计学意义(P0.05),各组螺壳中铜含量差异无统计学意义(P0.05)。以总SOD、CAT和Cu-ZnSOD活力为指标,运用折线模型分析,得出方斑东风螺对铜的需要量分别为5.83、5.61和5.87 mg/kg。     

4种重金属离子及其混合液对壶状臂尾轮虫的急性毒性试验

研究了铜、锌、镉、铅离子及其混合液对壶状臂尾轮虫(Brachionus urceus)的急性毒性影响，实验结果表明，Cu^2 、Zn^2 、Cd^2 、Pb^2 对壶状臂尾轮虫的24h LC50分别为83．18μg/L、4．27mg／L、7．60mg／L、23．44mg／L，将4种离子按照质量比120：20：6：1的比例配成混合金属溶液，其混合液对壶状臂尾轮虫的24h LC50为0．42mg／L。     

刁泉接触交代--中低温热液型银铜矿床矿物学特征

研究与成矿有关的矿石矿物成份,赋存状态及变化规律,根据矿石矿物的组成,粒度及其分析结果,对金属矿物生成顺序进行排列;找出了铜银元素在矿石矿物中的存在形式以及含铜银矿物的特征、变化规律.     

新显色剂四-(3-磺基-4-氯苯基)卟啉分光光度法测定微量铜

研究了新显色剂四-(3-磺基-4-氯苯基)卟啉在微酸性介质中,表面活性剂OP与CPC存在下测定微量铜的显色反应。络合物在波长420 nm处有最大吸收峰,摩尔吸光度系数为3.44×105L·mol-1cm-1,用双峰双波长光度法测定摩尔吸光系数为6.72×105L·mol-1·cm-1,铜含量在0.5~4.5μg/25 m L范围内符合比耳定律。方法应用于矿样中微量铜的测定,结果令人满意。     

ICP-AES测定金属元素铜活动态及其初步应用

金属元素活动态是我国5种深穿透地球化学技术中应用最广的方法之一。此方法是通过提取地表土壤一定深度介质中元素活动态的微弱隐伏矿信息而找寻隐伏矿,属于通过直接信息找矿,目前该方法的标准化程度不高。为将铜元素活动态应用于地质找矿,该文对铜元素4个活动态的相态(水浸出态、粘土吸附态、有机链合态、铁锰氧化物态)循序提取的条件及ICP-AES测定技术进行了研究,包括采样深度、分析样品粒度、样品存放时间、提取条件、测定干扰等,通过对铜活动态提取液处理方法的改进,提高了分析速度和分析数据的精度。由实验数据计算出各相态方法的检出限和精密度RSD(n=10),水浸出态为0.079mg/L,13.90%~22.49%;粘土吸附态为0.275mg/L,11.99%~23.29%;有机链合态为0.362mg/L,10.70%~57.27%;铁锰氧化物态为0.230mg/L,17.83%~38.61%。该方法操作方便,精密度较好,应用于碑楼隐伏铜矿的野外探测实验,探测结果所圈定的综合异常与实际矿体的水平投影相符,取得了较满意的试验效果,该方法可应用于不同地质景观区。     

土壤有效硫批量检测方法改进

土壤有效硫检测的常规方法是利用硫酸钡比浊法,鉴于规范推荐的测试步骤在批量土壤样品测试时效率较低,因此对常规方法进行了改进。加入2.0g氯化钡晶粒改为加入浓度为200g/L氯化钡溶液10mL;加稳固剂阿拉伯胶水溶液4mL改为加入浓度为6%甘油-乙醇(1+2)溶液5mL。通过对比实验,改进后检测方法比常规方法操作简便快捷,省时、省力、数据准确可靠,标准曲线线性相关系数达到0.9982。对土壤有效态成分分析标准物质土样GBW07459(ASA-8)、GBW07460(ASA-9) GBW07461(ASA-10)进行多次平行测试,测试结果全部在标准值范围内,且平行相对相差≤10%,证明改进后的检测方法可用于土壤有效硫的检测。     

Effects of biofertilizers and super absorbent polymers on plant growth and soil fertility in the arid mining area of Inner Mongolia,China

A pot experiment was conducted in the Institute of Tianlong Ecology of Baotou City in Inner Mongolia, China, to investigate the effects of the application of biofertilizers and super absorbent polymers (SAP) on plant growth and soil improvement in arid mining area soil. Two typical species, namely, Syringa oblata Lindl. (SO) and Medicago sativa L. (MS), were present in the Bayan Obo mining area and used as representatives of shrubs and herbaceous plants in the pot experiment. (1) Biofertilizers and SAP significantly increased the tree height, the ground diameter of SO, and the total biomass of MS and improved the soil fertility of the mining area, especially its biological fertility, compared with those of the control group (CK). The application of biofertilizers and SAP decreased the mining soil pH and significantly increased available nitrogen, available phosphorus, available potassium, and soil organic matter. (2) After 180 days of growth, the microbial population (bacteria, fungi, and actinomycetes) and soil microbial biomass carbon and nitrogen significantly increased. Microbial ratios C: N significantly decreased compared with those of CK. (3) T5 and T6 treatments with the following dosages might be the optimum selection for the improvement of the studied mining area soil: 20 g SAP + 15 g biofertilizers (SO), 100 g/m² SAP + 150 g biofertilizers (MS); 20 g SAP + 30 g biofertilizers (SO), and 100 g/m² SAP + 200 g biofertilizers (MS). This study provided a promising reference for conducting future field studies and the local vegetation restoration.     

水产饲料中三聚氰胺检测方法的优化

通过对高效液相色谱法(HPLC)测定水产饲料中三聚氰胺含量的方法进行优化,得到最佳色谱条件和前处理方法,建立了水产饲料中三聚氰胺的检测方法。结果表明:以体积比8∶92的乙腈、庚烷磺酸钠离子对试剂为流动相,柱温40℃,流速1.2 mL/min,以波长236 nm检测;以提取液为18 mL50%(φ)乙腈水+1 mL乙酸锌+1 mL1mol/L盐酸,淋洗液3 mL水和3 mL甲醇,洗脱体积6 mL作样品前处理。三聚氰胺加标回收率为85%～100%,相对标准偏差(RSD)小于5%,线性范围为0.2 mg/L～5.0mg/L,相关系数0.999 8,方法检出限为0.2 mg/kg。     

贵州普定灯盏河岩溶泉的硫同位素季节变化特征

通过对贵州普定后寨地下河补给区的灯盏河岩溶泉为期1年的泉水水文地球化学特征与水中SO2-4的硫同位素组成及季节性变化规律的分析,揭示灯盏河岩溶泉泉水中硫酸盐的来源及形成机理.结果表明:灯盏河岩溶泉的水化学类型主要为HCO-3·SO2-4 Ca2+型,具有很高的硫酸盐浓度,且变化幅度较大,SO2-4浓度为0.35~8.76mmol·L-1;灯盏河泉水SO2-4的硫同位素组成为(3.80~25.76)×10-3,反映泉水的硫同位素组成主要受土壤有机硫氧化和石膏岩层溶解的控制;泉水硫同位素组成季节性变化明显,表现为旱季大于雨季,且旱季变化平缓,主要受石膏溶解的控制,而雨季变化幅度较大,反映雨季地下水硫酸盐土壤有机硫源贡献的增加及其季节性差异.     

D_（001）树脂在酸性硫脲溶液中吸附、分离金银研究

本文研究了Ｄ_００１大孔阳离子强酸树脂从Ｈ_２ＳＯ_４－ＣＳ（ＮＨ_２）_２溶液中，富集及分离Ａｕ（Ｉ）、Ａｇ（Ｉ）的性能。表明在ｐＨ＝２．０左右，树脂对Ａｕ（Ｔｕ）￣＋_２、Ａｇ（Ｔｕ）￣＋_２（Ｔｕ＝硫脲）有良好的吸附性能，Ａｕ和Ａｇ的吸附容量分别为６１．１８ｍｇ／ｇ－Ｒｅｓｉｎ和９９．１１ｍｇ／ｇ—Ｒｅｓｉｎ。负载柱上的Ａｕ、Ａｇ可分别用ＮａＣＮ—ＮａＯＨ和Ｈ_３ＢＯ_３－ＮａＯＨ－Ｎａ_２Ｓ_２Ｏ_３定量洗脱。可进行一定程度的Ａｕ、Ａｇ分离。     

Membrane preconcentration of iron in seawater samples and on-site determination in spectrophotometry

A novel method for on-site determination of trace iron was developed using membrane preconcentration and spectrophotometric detection. Fe(Ⅱ)-ferrozine complex was reacted with cetyltrimethylammonium bromide (CTAB) to form a Fe(Ⅱ)-ferrozine-CTAB paired compound, which was collected on a membrane by filtration under vacuum. The membrane was immersed in 2 mL of ethanol-nitric acid and the absorbance of the solution measured for quantitative analysis. Various factors affecting the iron collection and determination were investigated. With different sample preconcentration volumes, the range of determination was broadened to 0.5-120 g/L. The detection limit of this method reached 0.19 g/L and the recoveries were between 97.2 and 109% when the concentration enrichment was about 45. The relative standard deviation (n = 7) was 1.9% for samples containing 10 g/L Fe. Twelve seawater samples were analyzed on-site using the proposed method, and two were also analyzed in inductively coupled plasma mass spectrometry. No significant difference was shown between the two methods by the Student’s t-test. The method has also been used on-site for iron enrichment experiments with phytoplankton and concluded to be simple, accurate and inexpensive.     

化学诱导对2株海洋真菌次级代谢产物及其生物活性的影响

【目的】以2株海洋真菌为研究对象,探究不同种类及浓度的化学表观遗传修饰剂对其次级代谢产物化学多样性和生物活性的影响。【方法】基于化学表观遗传修饰策略,采用两种不同的化学表观遗传修饰剂5-氮杂胞嘧啶核苷(5-azaC)和丁酸钠,分别对Penicillium sp.019和Aspergillus terreus ZN4-5-4两株海洋来源真菌进行表观遗传修饰。通过观察真菌在培养基中的生长状态变化,并根据薄层层析(TLC)指纹图谱、高效液相色谱(HPLC)图谱、乙酰胆碱酯酶(AChE)抑制、1,1-二苯基-2-三硝基苯肼(1,1-Diphenyl-2-picryl-hydrazyl,DPPH)自由基清除和卤虫致死活性筛选模型等技术手段,从中筛选出代谢产物丰富、AChE抑制活性与抗氧化活性产物丰富且毒性小的发酵培养条件。【结果】添加1 mmol/mL的丁酸钠诱导剂可使菌株019和ZN4-5-4的次生代谢产物的种类增加,且同时能提高该菌株次级代谢产物的AChE的抑制活性和DPPH自由基清除活性。因此,确定菌株019和ZN4-5-4的最优发酵条件均是添加浓度为1 mmol/mL丁酸钠的PDB培养基。【结论】化学表观遗传修饰策略指导下,添加诱导剂5-azaC或者丁酸钠对2株海洋真菌次生代谢产物的产生有影响。