Bi_2Fe_4O_9的制备与光催化性能分析

采用水热法制备磁性铁酸铋(Bi_2Fe_4O_9)光催化剂,利用X线衍射仪、扫描电子显微镜、紫外—可见漫反射等仪器对Bi_2Fe_4O_9的晶相、形貌、光吸收特性进行表征。结果表明:在紫外光或可见光下,Bi_2Fe_4O_9可有效降解亚甲基蓝(MB),且在紫外光下降解效果尤为显著,其表观速率常数可达2.422×10~(-2) min~(-1)。通过加入不同种类的捕获剂推断Bi_2Fe_4O_9的光催化机理,以及光催化过程中的活性物种,h~+与·OH为光催化降解过程中的主要活性物种。     

负载型纳米TiO_2光催化杀灭溶藻弧菌的研究

采用平均粒径约5nm,主要结构为锐钛矿型的纳米TiO2光催化剂,以泡沫型复合镍板为载体对纳米TiO2进行固定,并对固定后的纳米TiO2杀灭溶藻弧菌的能力进行了研究。结果表明:利用高压汞灯作为光源,以泡沫型复合镍板为载体的纳米TiO2对溶藻弧菌具有较强的杀灭能力;极少量过氧化氢的加入加快了纳米TiO2的杀菌速度;因此,负载型纳米TiO2在水产病害防治方面具有广阔的应用前景。     

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％。     

复合光催化剂Cu_2(OH)PO_4/Ni(OH)_2的制备及其光催化性能

采用水热合成法在Cu2(OH)PO4表面原位沉积Ni(OH)2,制备异质结型的复合光催化剂Cu2(OH)PO4/Ni(OH)2;利用X线粉末衍射仪(XRD)、紫外-可见漫反射光谱仪(UV-Vis-DRS)和扫描电子显微镜(SEM)等,对其相结构、光吸收性能和微观形貌进行表征.结果表明:该复合光催化剂具有良好的紫外光吸收特性,是一类新型的光催化剂.复合光催化剂在紫外光下可以有效降解亚甲基蓝(MB)溶液,当Cu2(OH)PO4与Ni(OH)2的摩尔比为0.2时,Cu2(OH)PO4/Ni(OH)2具有最大催化活性.根据光催化中加入不同活性物种牺牲剂的实验,推测该异质结型材料光催化过程中光生载流子的传输方向及活性物种.Cu2(OH)PO4/Ni(OH)2的催化活性增强主要归结为复合时在两者之间形成有效的异质结,结区的内建电场能够促进光生载流子的分离,同时·OH和h+在光催化降解过程中是主要的活性物种.     

O3处理时间与粗饲料纤维性物质成分变化关系的研究

将稻秆、麦秆、棉秆 3种粗饲料切成 4cm长 ,水分含量调节到 3 0 % ,用臭氧 (O3)处理 3 0 ,60和90min ,对照组不进行O3处理 ,以比较O3处理对 3种粗饲料纤维性物质成分变化的影响。结果表明 :O3处理能显著降低粗饲料纤维性物质成分含量 ,处理的时间越长 ,降低越多 ,60min前的降幅大于 60min以后的降幅。ADL含量高的粗饲料 ,经O3处理后降幅大。O3处理粗饲料 ,能降低纤维性物质成分含量 ,改善粗饲料的品质 ,提高其利用率     

SiO_2改性AlPO_4—5/Al_2O_3复合载体催化剂的表征及加氢性能

为了考察SiO_2对W-Ni催化剂加氢脱硫活性的影响,将SiO_2以硅溶胶形式引入AlPO_4—5/Al_2O_3复合载体,制备W-Ni催化剂,对改性的复合载体及催化剂进行BET、NH3-TPD、DRS及LRS方法表征,采用二苯并噻吩的模型化合物对催化剂脱硫活性进行微反评价。结果表明:将SiO_2引入AlPO_4—5/Al_2O_3复合载体,可改善活性金属与载体间的相互作用,提高催化剂的酸强度,促进金属组分的易还原性;SiO_2质量分数为12.0%时,催化剂的加氢活性最高,说明适当加入SiO_2有利于提高催化剂加氢脱硫活性。质量分数为12.0%的SiO_2改性复合载体制备的催化剂Cat-NiW/Si12AP对大庆催化柴油加氢评价结果表明,该催化剂具有良好的加氢脱硫、脱氮及芳烃饱和性能。     

地理栅格数据并行I/O的研究与实现

随着遥感和测绘技术的进步,日益增大的数据量和高效的数据I/O矛盾逐渐凸显。本文针对这个问题提出了地理栅格数据的一种并行I/O模式,并对该I/O模式进行了相应的编程实现。通过设计实验验证其正确性和效率,我们发现相比传统的栅格数据I/O库(GDAL库)而言,采用本文提出的并行I/O模式对应的I/O库将能同时保证结果的正确性和高效性。     

O3处理时间与粗饲料纤维性物质成分变化关系的研究

将稻杆、麦杆、棉秆3种粗饲料切成4cm长，水分含量调节到30％，用臭氧（O3）处理30，60和90min，对照组不进行O3处理，以比较O3处理对3种粗饲料纤维性物质成分变化的影响。结果表明：O3处理能显著降低粗饲料纤维性物质成分含量，处理的时间越长，降低越多，60min前的降幅大于60min以后的降幅。ADL含量高的粗饲料，经O3处理后降幅大。O3处理粗饲料，能降低纤维性物质成分含量，改善粗饲料的品质，提高其利用率。     

中国城市群臭氧污染时空分布研究

随着中国城市建设进程的加快,中国的臭氧（O₃）污染逐渐受到重视。城市群是人口大国城镇化的主要空间载体,是城镇化的主体形态。截至2017年3月底,国务院共先后批复了6个国家级城市群,并提出要优化提升东部地区城市群,培育发展中西部地区城市群。另外,新的城市规模划分标准以城区常住人口为统计口径,将城市划分为5类7档。为了研究中国O₃污染的时空分布特征以及O₃污染与城市群之间的关系,利用地理探测器（Geographical detector）和演化树模型对2014年6月到2017年5月共36个月的O₃监测数据进行时空分析。结果表明：中国O₃污染水平呈现上升趋势,并在2017年迅速增长,O₃已成为仅次于PM_2.5的第二大污染因子,且与PM_2.5在时间上呈“交错污染”的态势;O₃污染超标城市绝大多数集中在城市群区域,其中长江三角洲城市群、京津冀城市群、山东半岛城市群和中原城市群相对突出;O₃和PM_2.5均不超标的城市主要集中在北部湾城市群和海峡西岸城市群;城市群中人口规模大的城市O₃污染较为严重。     

用膨润土处理含铅离子废水的研究

用膨润土对模拟含pb2 离子的废水进行了试验研究.结果表明:膨润土是一种有效的吸附剂.其在粒径范围为200-300目,温度30℃左右,用量每1L含铅废水(50mg/1)为3g,pH值在大于7中性至碱性,振荡时间为45min的实验条件下,对废水中Pb2 去除效率高于97%.     

二价铁活化过硫酸盐去除水中苯胺

零价铁和硝基苯反应后生成二价铁和苯胺,而苯胺也是地下水污染物。硫酸根自由基具有强氧化性,可以降解苯胺。而二价铁可以活化过硫酸盐产生硫酸根自由基,进而去除苯胺。本文研究了二价铁浓度、过硫酸盐浓度、苯胺初始浓度、体系初始pH、反应温度等因素对二价铁活化过硫酸盐去除水中苯胺处理效率的影响。结果表明：①） Fe2＋活化过硫酸盐生成SO4-·能快速并有效氧化降解苯胺,对于目标浓度为1000 mg/L 的苯胺而言, Fe2＋浓度为3.3 mmol/L, Na2 S2 O8浓度为4.4 mmol/L时,对苯胺有较佳降解效果,苯胺的降解率为86.33％。②体系对较低浓度的苯胺降解效果较好,当污染物初始浓度由1000 mg/L降低到500 mg/L和100 mg/L时,苯胺降解率由86.33％升高为90.27％和97.16％。③初始pH对苯胺的降解率影响较大,中性条件下（ pH＝7左右）降解率较好,高初始pH （pH＝9,11）和低初始pH条件（pH＝3,5）下均低于中性条件下苯胺的降解效率。④体系的温度变化对降解率影响不明显。     

Enhancing effect of Fe2+ on the formaldehyde production from trimethylamine N-oxide decomposition catalyzed by the extract of Harpadon nehereus kidney

The effects of Fe2+ on the trimethylamine N-oxide (TMAO) demethylating activity of the Harpadon nehereus kidney extract were studied in this research.The activity of the kidney extract was presumably inhibited by ethylene diamine tetra-acetic acid (EDTA),which indicates that the kidney extract contains an enzyme or enzyme system with metal cations as activator.Activity of the kidney extract was enhanced significantly when Fe2+ was added into the model system in vitro.As the concentration of Fe2+ increased,the decomposing rate of TMAO increased rapidly until TMAO decomposed completely.The activity of the kidney extract was also enhanced by reductant such as ascorbic acid.Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) was employed to determine the content of total iron in a number of fishery products.Significant positive correlation between the contents of total iron and endogenous formaldehyde (FA) was found,especially in marine products.     

Synthesis of three-dimensional agaric-like biomorphic TiO2 by a facile method with Coscinodiscus sp. frustule

The paper aims to expand the application of natural marine algae.Marine diatoms,which have intricate frustule structures,can serve as bio-template for preparing three-dimensional materials.A simple and effective approach to synthesize the corrugated agaric-like biomorphic TiO 2 templated with frustule of Coscinodiscus sp.is reported.In the sol-gel preparation process,the titania-coating on the frustule is prepared through the deposition and condensation with the aid of acetylacetone(acac) as a controlling agent to make the precursor Ti(BuO) 4 hydrolyze slowly.The as-prepared titania-coated frustule and biomorphic TiO 2 is characterized by scanning electron microscopy(SEM) attached with energy dispersive X-ray spectrometer(EMAX) and X-ray diffraction(XRD).The microstructure of the corresponding titania nanoparticles appears to be sphere with the diameters distributed around 10 20 nm.The templating process is repeated for three cycles.Subsequently,the three-dimensional freestanding corrugated agaric-like biomorphic TiO 2 structure is obtained by a selective removal in the NaOH solution.As far as we known,the 3D freestanding corrugated agaric-like biomorphic TiO 2 with greatly increased surface area is obtained for the first time.     

J2EE平台下数据库的开发与优化

在J2EE平台下，后端数据库频繁交互，如果后端数据库耦合性差、总是迟迟不能响应，应用的可维护性、性能必将大受影响，所以数据库的开发尤其重要。从数据库映射、访问、优化等几个方面系统地阐述了数据库的设计规范。     

Degradation of natural resources by environmental pollution

Compared the total agricultural production (TAP) of the 5 counties in Huizhou City with that of the corresponding 5 counties in Zhaoqing City during the period from 1980 to 1996, it can be seen that the TAP growth rate of the 5 counties in Huizhou City had been a little higher than that of the 5 corresponding counties in Zhaoqing City before 1983, but has been becoming lower than the latter since 1984, and the agricultural production in Huizhou City has been gradually becoming lag behind that in Zhaoqing City since then. The TAP loss in Huizhou City kept above 3×10⁸ yuan every year since 1986. Detailed investigation shows that the acid rain caused by the atmospheric pollution may be the main cause for the lower productivity of the land in Huizhou City. The atmospheric pollution arisen from rapid and extensive development of the economy in the Zhujiang(Pearl) River Delta Region has already greatly reduced the load capacity of the natural resources in Huizhou City and severely affected the sustainable development of the region.     

Recovery of astaxanthin from discharged wastewater during the production of chitin

In this paper, studies were carried out to extract astaxanthin from discharged wastewater during the production of chitin and to reveal the scavenging effect of the obtained pigment on 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radical. Different ratios of dichloromethane/methanol (V/V) were used to extract astaxanthin. When the ratio of dichloromethane/methanol was 2:8 and the ratio between the mixed organic solvent (dichloromethane/methanol, 2:8, V/V) and wastewater was 1:1, the highest yield of pigment was obtained (8.4 mg/ 50 mL). The concentration of free astaxanthin in the obtained pigment analyzed by HPLC was 30.02%. The obtained pigment possessed strong scavenging ability on DPPH radical and IC50 was 0.84mg/ml.     

2018-08-25~29期间全球电离层TEC对地磁暴的响应分析

使用IGS提供的全球电离层地图对2018-08-26地磁暴期间TEC变化进行分析,利用滑动四分位距法提取全球TEC扰动特征,并初步探讨此次磁暴引起的电离层扰动响应机制。结果表明：1）磁暴主相期间,除北极地区外电离层TEC主要表现为正相扰动;在恢复相期间,电离层TEC在北半球呈现长期负扰,而在南半球则相反。2）磁暴期间全球电离层TEC扰动与热层成分O/N₂变化有关。星际磁场南向期间,东向快速穿透电场对全球日间电离层TEC正扰具有很大影响,高能粒子的沉降作用可能是高纬和极区TEC发生正扰的原因;夏冬季节环流会促进电离层在磁暴恢复相阶段的南北不对称响应。     

关于平果铝矿生产勘探问题的研究

岩溶堆积型铝土矿是国内新类型的铝土矿床,文章探讨该类型矿床的勘探类型,研究合理勘探网度,将地质勘探与生产勘探资料进行对比分析,简介生产勘探中一些成功经验