负载纳米水合氧化铁活性炭去除水中铅的实验研究

通过共沉淀法制备一种负载纳米水合氧化铁活性炭,研究其对铅的吸附性能、负载前后活性炭的结构的影响,并进行TEM和XRD表征分析。利用动态小柱实验探究不同p H值、进水浓度和空床接触时间对铅吸附能力的影响,同时比较负载前后活性炭处理实际河道水中铅的吸附穿透曲线。结果表明:无定型的纳米水合氧化铁成功负载于活性炭上,负载后的活性炭显著提高了铅的吸附性能,其对铅的吸附容量随p H值、空床接触时间的增大而增加,进水浓度的变化基本不影响铅的吸附容量。以实际河道水为处理对象,得出负载前后的活性炭穿透点运行的床体积分别为1233和11004,显著提高了9倍,表明负载纳米水合氧化铁活性炭可以有效去除实际水体中的铅,具有良好的应用前景。     

超细矿粉对混凝土界面区硫酸盐腐蚀的影响

为了研究骨料与水泥石界面区(ITZ)的组成及结构对混凝土抗硫酸盐腐蚀性能的影响,利用紫外分光光度计绘制了硫酸钠溶液浸泡混凝土试样的SO2-4浸入浓度/深度曲线,并辅以扫描电镜(SEM)和电子探针能谱(EDS)等对ITZ进行观测;同时利用XRD定量分析研究了混凝土本体相和界面相的水化产物富集的差异.结果表明:Ca(OH)2、钙矾石(AFt)等晶体富集于硫酸钠溶液浸泡后试样的ITZ,引起AFt二次结晶型的硫酸盐腐蚀破坏.在适量石膏的激发下,掺入超细矿粉(GGBS)可阻止AFt转变成单硫型水化硫铝酸钙(AFm),减少AFt二次结晶的生成,明显提高抗硫酸盐侵蚀能力,试样的同深度硫酸根浓度最低,抗硫酸盐侵蚀性能最好.     

硫铵结晶稠化器的优化设计

为解决硫铵结晶稠化器由于设计不合理造成的管线堵塞、溢流问题,通过对稠化器增加蒸汽吹扫、安装视镜、加大稠化器顶部空间、采用可调溢流挡板等措施,确保了管线的畅通、离心机进料的稳定,减少了硫胺产品中己内酰胺的夹带。     

电化学方法探讨三聚磷酸钛及磁性氧化铁在有机涂层中的缓蚀机制

本文利用电化学方法研究了在油漆涂层中添加三聚磷酸钛和磁性氧化铁对金属防护性能的影响。结果表明,三聚磷酸钛作为活性防锈颜料,添加在涂层中能够极大地改善涂层的防护性能,磁性氧化铁亦不失为一种较好的防锈颜料,但性能不及三聚磷酸钛。同时亦探讨了这两种颜料的可能防锈机理。     

PREPARATION OF ULTRAFINE NICKEL POWDER

ＰＲＥＰＡＲＡＴＩＯＮＯＦＵＬＴＲＡＦＩＮＥＮＩＣＫＥＬＰＯＷＤＥＲＣｈａｉＬｉｙｕａｎ；ＺｈｏｎｇＨａｉｙｕｎ（ＤｅｐａｒｔｍｅｎｔｏｆＮｏｎｆｅｒｒｏｕｓＭｅｔａｌｌｕｒｇｙ，ＣｅｎｔｒａｌＳｏｕｔｈＵｎｉｖｅｒｓｉｔｙｏｆＴｅｃｈｎｏｌｏｇｙ，...     

Ni3Al材料在O2／SO2／SO3气氛中的低温热腐蚀行为

用涂盐法并借助扫描电镜、光谱分析、金相、电子探针及Ｘ射线衍射等技术研究了Ｎｉ３Ａｌ金属间化合物在Ｏ２／ＳＯ２／ＳＯ３气氛中６００－８００℃温度范围内（Ｎａ，Ｋ）２ＳＯ４引起的低温热腐蚀行为。结果表明，Ｎｉ３Ａｌ发生了低温热腐蚀，其腐蚀速度在７５０℃呈现一最大值。热腐蚀的发生主要归因于多元共晶盐的形成。盐沉积加速了材料在空气中的氧化。ＣｏＣｒＡｌＹ涂层能改善合金的耐蚀性能。     

THERMODYNAMIC AND STRUCTURAL CHEMISTRY DISCUSSIONS FOR OXIDATIVE LEACHING OF Cu－Ni SULPHIDE ORE UNDER ATMOSPHERIC PRESSURE

ＴＨＥＲＭＯＤＹＮＡＭＩＣＡＮＤＳＴＲＵＣＴＵＲＡＬＣＨＥＭＩＳＴＲＹＤＩＳＣＵＳＳＩＯＮＳＦＯＲＯＸＩＤＡＴＩＶＥＬＥＡＣＨＩＮＧＯＦＣｕ－ＮｉＳＵＬＰＨＩＤＥＯＲＥＵＮＤＥＲＡＴＭＯＳＰＨＥＲＩＣＰＲＥＳＳＵＲＥ￥Ｗｕ，Ｗｅｎｊｉａｎ（Ｄｅｐａｒ...     

硫酸铵厂房和构筑物的腐蚀防护

与硫酸铵接触的部分建筑物和构筑物腐蚀严重，混凝土因腐蚀而剥落并露出钢筋，危害厂房的安全使用，通过对混凝土遭受腐蚀原因的分析，提出了相应的防护措施。     

硫酸盐干湿循环下带冷缝混凝土能量演化研究北大核心CSCD

为探究硫酸盐干湿循环作用下带冷缝混凝土受荷作用时的能量演化规律,制作了整浇和浇筑间隔0.25 d、0.5 d、1 d、7 d和28 d的带冷缝混凝土,基于单轴压缩实验及能量计算原理,研究了硫酸盐干湿循环对带冷缝混凝土强度和能量演化规律的影响。结果表明:带冷缝混凝土强度及损伤应力和峰值应力处弹性应变能与耗散能均随干湿循环呈先增大后减小的趋势,随着新混凝土与母体浇筑间隔的增加呈现减小的趋势;随着干湿循环次数的增加,损伤应力处储能水平Kad先减小后增加,说明损伤应力处储能水平越高,带冷缝混凝土越容易产生损伤,Kad可以作为混凝土破坏的预警指标。     

Adherence rates to ferric citrate as compared to active control in patients with end stage kidney disease on dialysis

Introduction: Oral phosphate binders are the main stay of treatment of hyperphosphatemia. Adherence rates to ferric citrate, a recently approved phosphate binder, are unknown. Methods: We conducted a post‐hoc analysis to evaluate whether adherence rates were different for ferric citrate vs. active control in 412 subjects with end stage kidney disease (ESKD) who were randomized to ferric citrate vs. active control (sevelamer carbonate and/or calcium acetate). Adherence was defined as percent of actual number of pills taken to total number of pills prescribed. Findings: There were no significant differences in baseline characteristics including gender, race/ethnicity, and age between the ferric citrate and active control groups. Baseline phosphorus, calcium, and parathyroid hormone levels were similar. Mean (SD) adherence was 81.4% (17.4) and 81.7% (15.9) in the ferric citrate and active control groups, respectively (P = 0.88). Adherence remained similar between both groups after adjusting for gender, race/ethnicity, age, cardiovascular disease (CVD), and diabetic nephropathy (mean [95% CI]: 81.4% [78.2, 84.6] and 81.5% [77.7, 85.2] for ferric citrate and active control, respectively). Gender, race/ethnicity, age, and diagnosis of diabetic nephropathy did not influence adherence to the prescribed phosphate binder. Subjects with CVD had lower adherence rates to phosphate binder; this was significant only in the active control group. Discussion: Adherence rates to the phosphate binder, ferric citrate, were similar to adherence rates to active control. Similar adherence rates to ferric citrate are notable since tolerance to active control was an entry criteria and the study was open label. Gender, race/ethnicity, nor age influenced adherence.