LC4铝合金呆扳手成形热力学参数的确定

通过试验研究了LC4铝合金呆扳手成形的温度、变形程度、变形速度、加热方式和加热速度等成形热力学参数与成形质量之间的关系。解决了试验过程中出现的一些问题,确定了最佳成形工艺参数为:始锻温度400～450℃、终锻温度350℃左右,第1阶段的变形量为30%～50%,第2阶段的变形量为75%。     

玉米铝（Al）胁迫研究初报

通过试验和分析，研究Ａｌ胁迫下的玉米生物性状和主要生理特性，明确活性铝浓度与玉米根系特征及地上部农艺性状之间存在极显著或显著的反比相关；活性铝的存在，降低玉米茎叶Ｎ、Ｐ、Ｋ等养分含量，提高叶片脯氨酸累积量；脯氨酸含量可作为玉米耐Ａｌ性的生理指标．     

番茄柱式无土栽培研究

在立柱密度为 80cm× 80cm的”树林”式柱式无土栽培区种植番茄 (LycopersicumMill) ,品种是洋杂 2号和90 6 ,面积各有 5 4 0m2 (在非自控玻璃温室内 ) ,各含 6 36根立柱 ,每根柱种 3层共 9株 ,总共各有 5 72 4株 .番茄生长期间 ,柱上植株始终保持塔形排列 ,每株留 2穗果约 6只番茄 ,在不影响结果情况下注意去顶、剪叶和去除营养枝 ,以保持柱间有良好透光 .此外 ,在两行立柱之间地面 (除走道外 )铺设中高 10cm倒V字形双面铝 (Al)膜反光体 ,可使柱高 10 0cm以下的光照量增加 5 0 %左右 ,并超过了番茄的光合需要保持量E为 6 0 0～ 70 0 μEm-2 s-1[2 ] 的要求 .立柱由基质型盆钵组成 ,盆钵中的基质有陶粒、用过的香菇菌棒碎料加珍珠岩加有机肥料和难溶磷铁肥 ,于循环水中加入盆钵中没有的成分组成完全的平衡营养系统以循环浇灌 ,结果培养出了粗壮结果良好的的植株 .番茄洋杂 2号亩产为 5 184kg,是对照(深流栽培 )的 2 .4倍 ,又比土栽培的产量高 30 % ;品种 90 6亩产为 5 2 34kg,是对照土栽培的 2 .2倍 .图 2表 3参 2     

铝暴露对雏鸡免疫功能的影响

以1周龄伊莎雏鸡为实验对象,采用连续腹腔注射的方法,研究了铝暴露对雏鸡免疫功能的影响.实验设对照、低、中、高4个剂量组,暴露剂量分别为0、18.31、27.47、36.62mg·kg-1·d-1(Al3+),暴露60d后,检测雏鸡血清、脾脏和法氏囊中元素Al、Fe、Zn、Mn、Ca、Cu含量及血清补体(C3、C4)、白细胞介素-2(IL-2)和肿瘤坏死因子-α(TNF-α)含量.结果表明,暴露60d后,与对照组雏鸡相比,低、中、高剂量组雏鸡血清、脾脏和法氏囊中Al、血清补体C4和TNF-α含量均有不同程度地升高,而Fe、Zn、Mn、Ca、Cu、C3和IL-2含量均有不同程度地降低;随着铝暴露剂量的增加,Al、C4和TNF-α含量逐渐升高,而Fe、Zn、Mn、Ca、Cu、C3和IL-2含量逐渐降低,均存在一定的剂量-效应关系.上述结果表明,铝暴露对雏鸡免疫功能具有明显的抑制作用.     

超声波强化零价铁/过硫酸钾体系处理柠檬酸镍络合废水

以柠檬酸镍络合废水为目标废水,考察了超声波(US)强化零价铁(Fe~0)/过硫酸钾(PS)体系的初始pH、过硫酸钾用量(C_(PS))、超声波功率、零价铁与过硫酸钾质量比(m)、零价铁粒径(d_(Fe~0))对镍去除的影响.结果表明,在超声波功率为600 W,pH为3,过硫酸钾用量为0.45g·L~(-1),Fe~0∶PS(质量比)为0.8,零价铁粒径为75μm的条件下反应60 min时,镍的去除率可以达到100%.不同体系的对照实验和反应前后零价铁SEM、EDS分析结果表明,US/Fe~0/PS体系效果明显优于US/Fe~0、US/PS和Fe~0/PS体系,超声波对Fe~0/PS体系具有强化作用,能促进零价铁持续释放具有催化作用的Fe~(2+).最后,通过红外光谱和紫外光谱分析了柠檬酸镍破络机理.TOC变化规律表明,体系矿化速率低于体系中柠檬酸的降解速率,说明柠檬酸镍降解首先是一个快速破络过程,随后是破络后的中间产物进一步降解矿化.     

Preparation and characterization of ZnO/ZnS hybrid photocatalysts via microwave-hydrothermal method

The photocatalytic performance of ZnO/ZnS hybrid nanocomposite was largely higher than that of the mere ZnO or ZnS nanoparticles, but the complicated procedure and misdistribution of final products limited its large-scale productions. The exploration of a novel synthesis route of ZnO/ZnS hybrid photocatalysts with high catalytic performance is becoming a crucial step for the large-scale application of ZnO/ZnS hybrid photocatalytic technique. Preparation and characterization of nanosized ZnO/ZnS hybrid photocatalysts were studied in this paper. The photocatalysts were obtained via microwave-hydrothermal crystallization with the help of sodium citrate. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), particle size distribution (PSD), and Fourier transformed infrared spectroscopy (FT-IR). The results indicated that so-synthesized ZnO/ZnS samples consisted of the high pure cubic (sphalerite) ZnS and hexagonal ZnO nanocrystallines with a narrow particle size distribution. The possible formation mechanisms of ZnO/ZnS nanocrystallines were mainly attributed to the superficially protective effect of citrate. The photocatalytic experiments demonstrated that the ZnO/ZnS photocatalysts exhibited a higher catalytic activity for the degradation of acid fuchsine than other monocomponents.     

慢性铝暴露致大鼠骨与软骨损伤胶原途径的动态分析

为了探讨慢性铝暴露致大鼠骨与软骨损伤胶原途径的机制及胶原代谢水平,实验将100只4周龄清洁级Wistar大鼠随机均分成染铝组(430mg·L-1Al3+)与对照组(蒸馏水),通过饮水染铝,每隔30d处死染铝大鼠和对照大鼠各10只,设立5个观测点,最长染铝时间为150d.同时,用电子秤每30d称大鼠体重1次;用火焰原子吸收分光光度法测定血清、骨与软骨中铝含量;用固相夹心ELISA法检测血清中Ⅰ型前胶原羧基末端前肽(PICP)、Ⅰ型胶原C末端肽(CTX-Ⅰ)、Ⅱ型胶原(collagenⅡ)和Ⅱ型胶原C末端肽(CTX-Ⅱ)含量.结果表明,大鼠铝中毒模型复制成功;随着铝暴露时间的延长,染铝组大鼠体重在染铝60d后显著低于对照组(p0.01);染铝组血清、骨与软骨中铝含量逐渐升高,显著高于对照组(p0.01);PICP、Ⅱ型胶原合成量呈逐渐下降趋势,且显著低于对照组(p0.05,p0.01);CTX-Ⅰ和CTX-Ⅱ含量持续维持在高水平,分别在铝暴露90d、60d后显著高于对照组(p0.01).说明长时间铝暴露可致铝在骨与软骨中蓄积,并使骨与软骨中结构性胶原减少,引发骨与软骨损伤.     

Competitive and cooperative adsorption of arsenate and citrate on goethite

The fate of arsenic in natural environments is influenced by adsorption onto metal (hydr)oxides. The extent of arsenic adsorption is strongly a ected by coexisting dissolved natural organic acids. Recently, some studies reported that there existed competitive adsorption between arsenate and citrate on goethite. Humic acid is known to interact strongly with arsenate by forming complexes in aqueous solution, hence it is necessary to undertake a comprehensive study of the adsorption of arsenate/citrate onto goethite in the presence of one another. The results showed that at the arsenate concentrations used in this study (0.006–0.27 mmol/L), citrate decreased arsenate adsorption at acidic pH but no e ect was observed at alkaline pH. In comparison, citrate adsorption was inhibited at acidic pH, but enhanced at alkaline pH by arsenate. This was probably due to the formation of complex between arsenate and citrate like the case of arsenate with humic acid. These results implied that the mechanism of the adsorption of arsenate and citrate onto goethite in the presence of one another involved not only competition for binding sites, but the cooperation between the two species at the watergoethite interface as well.     

Removal of fluoride from water using aluminium containing compounds

Batch adsorption studies were undertaken to assess the suitability of aluminium titanate (AT) and bismuth aluminate (BA) to remove fluoride ions from water. The e ect of pH, dose of adsorbent, contact time, initial concentration, co-ions and temperature on fluoride removal e ciency were studied. The amounts of fluoride ions adsorbed, at 30°C from 4 mg/L of fluoride ion solution, by AT and BA were 0.85 and 1.55 mg/g, respectively. The experimental data fitted well to the Freundlich and Langmuir isotherms. Thermodynamic parameters such as H0, S 0 and G0 indicated that the removal of fluoride ions by AT was exothermic and non-spontaneous while that by BA was endothermic and spontaneous. Fourier transform infrared (FT-IR) analysis and X-ray di raction (XRD) patterns of the adsorbent before and after adsorption indicated that fluoride ions were chemisorbed by these adsorbents.     

铁镁质尾矿中的钙镁浸取效果优化

铁镁质尾矿含有丰富的钙镁,利用浸取剂可以促进铁镁质尾矿中钙镁的释放,使这些尾矿成为固定CO2的材料。尾矿中钙镁的浸出率大小跟多个因素相关,如何寻求浸取钙镁的最优化条件,是有效利用铁镁质尾矿的重要内容。考虑环境友好的方案,采用EDTA、柠檬酸和柠檬酸钠浸取尾矿中的钙镁,并对比了不同条件下的浸取效果。通过比较,显示柠檬酸钠的浸取效果较好,在此基础上利用响应面法对粒度、pH值、固液比等主要影响因子进行优化处理。当反应液的pH=1,尾矿粒度<75μm,固液比为2.6∶100时,模型预测实验尾矿淋滤的Mg2+浓度为143.4 mg/L,Mg达到最佳溶出率2.03%。实验模型的预测精度良好,表明响应面法适用于尾矿的浸取实验优化。