Study on the Photocatalyzing Properties of TiO2 under different Roasting Temperature

We study the photocatalyzing properties of TiO 2 and compare their different crystal structures in different roasting temperature.It shows that the most efficient crystal structures can be determined and it have a satisfactory photocatalyzing properties.The principle that roasting temperature inflict to the photocatalyzing properties of TiO 2 was present.     

太阳光下TiO2光催化降解毒死蜱的动力学研究

笔者以太阳光为光源,研究了纳米TiO2降解毒死蜱的反应动力学,考察了纳米TiO2用量、毒死蜱起始浓度及溶液pH值对毒死蜱光催化降解速率的影响,旨在为将来实际生产中降解蔬菜、粮食、水果及农药废水中毒死蜱残留的污染提供依据。结果表明,TiO2最佳用量为50 mg/L;毒死蜱初始浓度越大,降解速率常数越小;在碱性条件下,有利于降解反应的进行。试验条件下毒死蜱的光催化降解符合一级反应动力学规律。     

纳米TiO2光催化降解苹果和洋李中毒死蜱残留的效果研究

为了利用光催化降解剂降低甚至消除农产品的农药残留,解决食品安全问题。本研究以水果中的有机磷农药残留为研究对象,探索了纳米TiO2粉体和水凝胶对苹果和洋李中毒死蜱残留的光催化降解效果。结果表明：二者均能很好的降解苹果和洋李中的毒死蜱残留,TiO2水凝胶的光催化效果稍优于纳米TiO2粉体。纳米TiO2本身无毒,光催化活性高,作为光催化降解剂在降低或消除农产品中的有机磷农药残留这一领域具有广阔的发展前景。     

TiO2 Photocatalysis and its Effect of Sterilizing and Killing Bacterium in Low Temperature Equipment

Some small particles can be produced from TiO 2 by using photocatalytic reaction. These small particles have high oxidation ability and can be usedi n refrigeration equipments in order to sterilize and kill bacterium. The principle of TiO 2 photocatalysis and the actions of sterilizing and killing bcterium were introduced. It is explained that different structures of TiO 2 have different photocatalytic performances and clarify the ways of combining large band gap semiconductor with small band gap semiconductor and doping impurity to enhance TiO 2 photocatalytic efficiency. Some problems of TiO 2 photocatalysis and application prospects were put forward.     

Research on Blocking and Flooding Behaviours of BF Slag Containing High TiO 2 in Blast Furnace

Smelting process of BF has been patterned with the high-temperature melting-dropping furnace in laboratory,blocking and flooding behaviours of slag containing high TiO 2 in BF have been tested,influences of gas velocity,content of TiO 2,reduced degree of TiO 2 and interface properties of slag-coke on blocking and flooding of molten slag in BF have been researched.     

Pr 3+/TiO2催化剂的制备及光催化性能分析

采用溶胶凝胶法制备了不同浓度、不同煅烧温度下Pr 3+掺杂TiO2光催化剂。对所制样品进行XRD、FT-IR、SEM表征,通过降解碱性品红溶液来测试样品的光催化性能。结果表明稀土Pr 3+掺杂TiO2能细化晶粒,提高热稳定性;在400 ℃下煅烧,摩尔比为n(Pr 3+)/n(TiO2)=0.2%的催化剂,加入氧化剂1 mL30%的双氧水,可以抑制电子和空穴复合,提高催化性能,在无灯源照射条件下,催化时间120 min,降解率达到100%。     

Effect of Metal Ion Adulterant on the Photocatalytic Degradation Properties of TiO2 Photocatalyst

TiO_ 2 photocatalyst can degrade organic pollutant in waste water efficiently. Metal ion-doped TiO_ 2 nanoparticles are prepared with different doping amount by sol-gel method. The prepared sample are evaluated by the photo-catalytic oxidation degradation experiment of methyl orange. The experiment results indicate that the photo-catalytic activities of Cr~(3+)-doped TiO_ 2 are photoactive than bare TiO_ 2, and that in the Cr~(3+)-doped TiO_ 2 system, 1.0% is optimal amount of doping. Furthermore, it is studied that the degradation rate of methyl orange can reach 92% in UV light of 4 hours and 85% in visible light of 6 hours.It can be expected that M~(n+)- TiO_ 2 photocatalyst is widely applied to the degradation of organic pollutant in waste water treatment.     

The removal efficiency of algal intracellular organic matter in Tai Lake by UV/immobilized TiO2

The immobilized TiO2 film loaded on fiberglass mesh is prepared by sol-gel method, and the analysis result of X-ray diffraction (XRD) shows that the crystalline phase is anatase. On the basis of UV/TiO2 system, the degradation results and effect factors of algal intracellular organic matter(IOM) in Tai Lake are studied. The results show that the degradation of IOM is much harder by photocatalytic oxidation in comparison with humic acid(HA). In 60 min, the IOM degradation of UV254 and DOC are 33.3% and 19.1%, but the HA solution are 96.6% and 57.3% respectively. The reason lies in that IOM is mainly comprised of macromolecular hydrophilic organic matter, containing more amino structures, while HA is strongly hydrophobic organic matter, containing more aromatic structures. Meanwhile, the degradation of IOM is improving as the increase of light intensity to a certain extent; the best degradation rate of IOM appears at pH=6.7.     

CaO-B2O3-SiO2-TiO2系保护渣配位结构的计算模拟

针对新型无氟保护渣CaO-B2O3-SiO2-TiO2四元渣系,采用分子动力学模拟的方法,对该保护渣系的微观结构进行了模拟计算,分析了CaO-B2O3-SiO2-TiO2渣系的配位结构,并考察了TiO2含量对保护渣配位结构的影响规律。研究表明：该渣系中硼的配位结构只存在三配位的三角体和四配位的四面体,而Ti与O之间主要以六配位的八面体结构形式存在;随着TiO2含量的增加,保护渣微观结构中Si、B、Ti的配位形式将发生明显变化,分别向四配位结构、三配位结构及五配位结构转化。     

纳米TiO2光半导体溶胶对植物光合机能的影响

TiO₂半导体颗粒的光催化机理类似于人工模拟光合作用,笔者初步探讨了其在植物体上对光合机能的影响;以锐钛型纳米TiO₂光半导体溶胶为材料,在栽培试验中,对黄瓜喷施不同浓度的纳米TiO₂溶胶,然后测定光合参数、根系活力及叶片丙二醛含量的变化;结果表明,黄瓜叶片喷施一定浓度的纳米TiO₂溶胶材料后,在叶片表面形成透明、连续、稳定的TiO₂薄膜,能显著促进光合速率的增加,同时根系活力得到提高。这为纳米TiO₂光半导体材料在农业上的应用提供了一定的理论依据和技术参考。     

红薯粉对面包面团流变学特性的影响

通过改变混粉(红薯粉和小麦粉)中红薯粉添加量,进行面包面团粉质试验和拉伸试验,以探讨红薯粉对面包面团流变特性的影响。结果表明,随着红薯粉添加量的增加,面团的吸水率和弱化度不断增大,在0～10%变化缓慢,超过10%变化显著;面团的形成时间、稳定时间、评价值、面团的延伸性、抗拉伸阻力、抗拉伸面积、最大抗拉伸阻力具有不同程度的下降,在0～10%变化缓慢,超过10%变化显著;拉力比数随红薯粉的增加不断减小,在0～8%变化缓慢,超过8%后变化显著。综合考虑红薯粉添加量应不超过8%。     

红薯粉对面包面团流变学特性的影响

通过改变混粉(红薯粉和小麦粉)中红薯粉添加量,进行面包面团粉质试验和拉伸试验,以探讨红薯粉对面包面团流变特性的影响.结果表明,随着红薯粉添加量的增加,面团的吸水率和弱化度不断增大,在0～10％变化缓慢,超过10％变化显著;面团的形成时间、稳定时间、评价值、面团的延伸性、抗拉伸阻力、抗拉伸面积、最大抗拉伸阻力具有不同程度的下降,在0～10％变化缓慢,超过10％变化显著;拉力比数随红薯粉的增加不断减小,在0～8％变化缓慢,超过8％后变化显著.综合考虑红薯粉添加量应不超过8％.     

Effect of Fe3 -doping on Photocatalytic Activing of TiO2 Thin Film for Degradation of Phenol

The transition metal ion-doped TiO_2 filmare prepared with Sol-Gel method, and the effects of doping different metal ions on the ability of TiO_(2)in photocatalyzing degradation of phenol are studied. The results show that doping of Fe~(3+)in TiO_2nanoparticles made photocatalytic efficiency increase, the effects of concentration of doped ions on photocatalytic performance are discussed.     

不同干燥处理对马齿苋总酚含量及其抗氧化性的影响

分别采用热风干燥法、真空微波干燥法和真空冷冻干燥法处理马齿苋,测定马齿苋粉甲醇提取液的总酚含量、总抗氧化能力、还原能力、DPPH·清除能力、羟自由基清除能力和超氧阴离子自由基清除能力,研究不同干燥方法对马齿苋粉总酚含量和抗氧化性的影响。结果表明,真空冷冻干燥法制得的马齿苋干粉样品中总酚含量显著高于真空微波与热风干燥样品;不同的干燥方法对马齿苋粉的抗氧化性有明显影响,真空冷冻干燥法制得的马齿苋粉甲醇提取液的总抗氧化能力、还原能力、DPPH·与羟自由基清除能力显著高于真空微波和热风干燥法制得的马齿苋粉(P0.05),但真空冷冻干燥样品与真空微波干燥样品对O_2~-·的清除率无显著差异,综合考虑产品品质与加工成本,采用真空微波干燥法更为合理。     

Influences on Engineering Properties of AS Firming Agent Modified Soil by Freeze-thaw Cycles

To study the freeze-thaw durability of Aught-Set(AS) firming agent modified soil, a series of triaxial tests were conducted. The mutual relationships between stress-strain relationship, static strength, dynamic modulus and critical dynamic stress of AS firming agent modified soil and curing time, freeze-thaw cycles, cooling temperature were deeply analyzed. The results show that the unconfined compressive strength of 7 d is 75% than that of 28 d. The stress-strain curves of AS firming-agent modified soil are strain-softening and in brittle failure shape. The static strength, critical dynamic stress and resilient modulus decrease in exponential form with the increase of freeze-thaw cycles, and after 6 cycles of freezing and thawing, the trend is stable. Under the same dynamic stress, the cumulative plastic strain of samples develop from stable state to failure because of freezing and thawing. After many times of freeze-thaw cycles, the lower the negative temperature, the little influence on the mechanic properties.     

纳米氧化锌和纳米二氧化钛对尾草履虫急性毒性效应的比较研究

[目的][方法] 本研究以原生动物尾草履虫（Paramecium caudatum）为实验对象, 对目前广泛应用的两种纳米材料,纳米二氧化钛（TiO2）和纳米氧化锌（ZnO）的24小时急性毒性进行了比较研究,分析了草履虫在两种纳米材料胁迫下抗氧化酶活性的改变,并结合两种纳米材料的超微形态,探讨了纳米材料毒性效应的机制,为两种纳米材料的环境毒性监测与评价提供依据。[结果]结果显示：对尾草履虫的24小时半数效应浓度(24h-EC50)分别为51.580mg·L-1（TiO2）、0.444mg·L-1（ZnO）;最低有影响浓度(24h-LOEC)分别为1.712mg·L-1（TiO2）、0.352mg·L-1（ZnO）;以EC50浓度24小时胁迫尾草履虫,获得抗氧化酶活性改变为：超氧化物歧化酶(SOD),过氧化氢酶(CAT)和过氧化物酶(POD)活性与对照组相比有不同程度的改变,经成对检验分析,两种纳米材料对尾草履虫的POD酶表现出较为明显的抑制作用。[结论]上述结果表明：纳米氧化锌对草履虫的24小时急性毒性大于纳米二氧化钛,这与纳米氧化锌对草履虫抗氧化酶的抑制作用更强,以及纳米氧化锌(30nm)的超微形态相较于纳米二氧化钛(25nm)更加纤细和尖锐有关;本研究获得的24小时急性毒性指标可用于监测和评价两种纳米材料的环境毒性,并为纳米材料的环境容量和生态安全阈值确定提供参考。     

糖诱导桃果实园片果实苯丙氨酸解氨酶活性上升和酚类物质积累的研究

为了探讨OPPP途径与苯丙烷类代谢途径的关系,使用G6PDH的底物和产物以及蔗糖温育分别处理桃果肉圆片,测定了苯丙烷类代谢的关键酶--苯丙氨酸解氨酶的活性变化,以及酚类物质含量的变化。试验结果显示,葡萄糖-6-磷酸、6-磷酸葡萄糖酸、葡萄糖和蔗糖都可以提高PAL活性,相应的总酚和总类黄酮含量也明显增加。而葡萄糖的类似物,2-脱氧葡萄糖的效应和对照相似,对PAL活性和总酚、总类黄酮的含量影响很小。     

KH_2PO_4渗调处理恢复和提高榉树种子活力的研究

采用不同浓度的KH_2PO_4处理常温贮藏12个月和18个月的榉树种子,结果表明:KH_2PO_4处理可提高榉树种子的发芽势、田间出苗率、活力指数及细胞膜系统的完整性,提高了种子的活力.在一定范围内,随着KH_2PO_4处理浓度的增加,榉树种子的活力也相应增加,KH_2PO_4处理浓度以3 g/L最佳,处理时间为24 h.     

Partial discharge pattern recognition based on S transform and two-directional 2DPCA

A new feature extraction method is proposed to recognize different types of partial discharge (PD) signals. Firstly,four typical categories of PD artificial defect models are made and S transform (ST) is employed to obtain a time-frequency representation of the recorded UHF signals. Then,two-directional two-dimensional principal component analysis ((2D) 2PCA) is applied to compress the ST amplitude (STA) matrix to extract features. Finally,support vector machine (SVM) combined with particle swarm optimization (PSO) algorithm is introduced to accomplish the recognition of experimental samples. Classification results demonstrate that the average recognition rate of (10,5) combination is the highest while the one of (5,5) combination is the lowest among four kinds of feature dimension combinations. Moreover,PSO can obviously improve the classification performance of SVM. Specifically,all the average recognition rates of PSO-SVM are higher than 94.43%and the maximum value comes to 97.67%. Therefore,the feature sets extracted by ST and (2D) 2PCA can not only achieve dramatic dimension reduction,but also retain the major information of original data. It is proved that the proposed algorithm can obtain ideal results in PD pattern recognition.     

纳米TiO_2——壳聚糖复合膜的功能特性与应用研究

纳米TiO2用表面改性剂月桂酸钠改性后,以溶液共混法制备了壳聚糖—纳米TiO2复合膜,并测试了其吸水率、透光率、力学性能和抑菌性能,进而探讨了复合膜应用于金秋梨保鲜的效果。结果表明,与单膜相比,壳聚糖—纳米TiO2复合膜的拉伸强度提高15.0%,断裂伸长率提高27.2%,直角撕裂强度提高35.6%;抑菌性能明显高于壳聚糖单膜及对照;同时,复合膜中,壳聚糖与纳米TiO2微粒间存在较强的氢键作用,从而使TiO2和壳聚糖之间有较好的界面作用,持水率和透光率得到提高,增强了果蔬保鲜效果,使金秋梨室温条件下的保鲜时间明显延长。