不同有机物对硝酸盐氮测试的影响

研究了红糖、葡萄糖、乙酸钠、甲醇、乙醇、乙酸、丙酸、丁酸、正戊酸、混合有机溶剂等10种不同有机物对麝香草酚光谱法和离子色谱法测试硝酸盐氮的影响。结果表明,溶液中含有红糖或葡萄糖时,均会对麝香草酚法测试硝酸盐氮造成影响,使得测试结果偏大;在无硝酸根离子存在时,红糖和葡萄糖的质量浓度与硝酸盐氮的测试浓度非线性相关;而乙酸钠、甲醇、乙醇、乙酸、丙酸、丁酸、正戊酸和混合有机溶剂则对麝香草酚法测试硝酸盐氮没有影响。实验发现,红糖和葡萄糖在浓硫酸的作用下与麝香草酚发生Molisch反应,形成有色复合物和红棕色不溶性沉淀。实验采用离子色谱法测试硝酸盐氮时,红糖和葡萄糖等糖类有机物对测试结果均无影响。     

紫外分光光度法测定核酸含量的影响因素分析

选择寡聚核苷酸、鲑鱼精单链DNA、小牛胸腺双链DNA标准物质为样本,系统研究了溶液pH、苯酚、丙酮、蛋白质、多糖等对紫外分光光度法测量结果的影响情况,另外考察了核糖核酸(RNA)和脱氧核糖核酸(DNA)的相互影响情况。研究发现基于分光光度法的核酸定量分析,易受溶液pH、苯酚、丙酮、蛋白质、多糖等的影响,另外,DNA和RNA之间也会相互干扰。因此,紫外分光光度法测定核酸含量时,特别是该方法用于核酸标准物质特性量值确定时,需要样品高度纯化,pH确定的条件下才能保证测量结果的准确可靠。     

铱磷光配合物Ir(dfppy)2(phbudio)的合成及表征

以氯桥二聚体[Ir(dfppy)2(μ-Cl2)]2、1-苯基-1,3-丁二酮为原料合成了一种铱磷光配合物Ir(dfppy)2(phbudio)，产率86.0%，并通过元素分析、核磁共振谱、质谱和红外光谱表征确认了目标产物的化学结构。通过紫外-可见吸收以及荧光光谱对其光物理性质进行测试，其常温最大发射位于522 nm处，显示发射强烈的绿光，初步推测该铱磷光配合物发射可能来自金属铱到环金属配体和辅助配体的电荷转移(MLCT)跃迁。     

Chemical conversion of Calophyllum inophyllum oil into bio-hydrocarbons fuel over presulfided NiMo/Al2O3 catalyst

Chemical conversion of Calophyllum inophyllum oil (raw oil) over presulfided NiMo/Al₂O₃ catalyst was conducted to generate organic liquid products (OLP) containing bio-hydrocarbons (OLP-1). Reacted in ±273 mL autoclave for 200 minutes at 375°C, P_H2 of 1 MPa, and 1% of catalyst loading, the raw oil was converted into 78.24% OLP-1 with a heating value of 47.93 MJ/kg. The OLP was refined through distillation and grouped into boiling point (bp) range as 13.9% of gasoline (bp at 72.6°C-184°C), 10.8% of kerosene (bp at 184.1°C-235°C), 47.9% of diesel oil (bp at 235.1°C-400°C), and 26.3% of heavy fractions (bp at 400.1°C-688.5°C). Besides OLP-1, oxygenated compounds (OLP-2) were also contained as by-products. The catalytic reaction mechanism of C inophyllum oil was also confirmed using fatty acid model compounds. The OLP-1 mainly consisted of paraffinic hydrocarbons of C10-C18.     

Iron(II) Sulfate(VI) from Titania Production as a Raw Material for Preparation of Hydrogen Sulfide Sorbents

A hybrid sorbent material for removal of hydrogen sulfide from air was developed. The material is based on activated carbon and iron compounds obtained from waste iron(II) sulfate(VI) heptahydrate. The iron salt is deposited on the carbonaceous support and subjected to oxidation (Fe²⁺ to Fe³⁺) using atmospheric oxygen under alkaline conditions. An effect of H₂O₂ addition to the process on the composition of the resultant material was also examined. X-ray diffraction (XRD) analyses confirmed easy conversion of waste FeSO₄·7H₂O to iron oxides Fe₃O₄ and FeOOH. The activated carbon supporting iron oxides revealed a higher efficiency in H₂S elimination from air compared to the commercial activated carbon, without any modification.     

某铜铅锌多金属硫化矿选矿试验研究

对某富含金银等贵金属的复杂铜铅锌多金属硫化矿进行了选矿试验研究。以BK916作铜捕收剂、BK906作铅捕收剂, 采用铜优先浮选-铅浮选-锌硫混合浮选-锌硫分离工艺回收主要有价元素, 获得了铜精矿铜品位24.26%、回收率58.21%, 铅精矿铅品位70.75%、铅回收率86.55%, 锌精矿锌品位51.53%、锌回收率89.44%, 硫精矿硫品位39.84%、回收率38.03%的良好选矿指标; 铜、铅、锌、硫4种精矿产品中金总回收率92.16%、银总回收率89.44%。     

某复杂铜硫矿浮选分离与综合回收试验研究

某复杂铜硫矿原矿硫铁含量高,现场为高碱工艺流程,铜硫分离困难且金银综合回收效率低。采用硫化钠预先活化,“石灰+羧化壳聚糖”作黄铁矿和磁黄铁矿抑制剂,粗选pH=8.5,经一粗两精三扫优先浮选流程可得到含铜24.63%、含金3.41 g/t、含银952.05 g/t,铜回收率84.45%、金回收率32.58%、银回收率75.70%的铜精矿。羧化壳聚糖为清洁高效有机高分子化合物,能高效选择性抑制硫铁矿,在提高主金属铜回收率的同时,伴生金银矿物得到了高效综合回收。     

C38+N2非调质钢曲轴法兰开裂原因分析

某厂的C38+N2非调质钢曲轴,在装机测试压力时法兰部位开裂。通过化学成分分析、金相检验、断口检验、能谱分析及硫印试验等研究了曲轴开裂的原因。分析结果如下:①材料化学成分和法兰部位淬硬层深度均符合要求;②断口上部为准解理断裂,下部为“朽木状”撕裂;③在锻造分模面有硫化物聚集,甚至有长达1mm的以MnS为主的超长硫化物。硫化物聚集割裂基体材料是曲轴开裂的主要原因,曲轴锻后晶粒粗大,法兰的螺孔部位厚度较薄,是其开裂的次要原因。     

Integrating superstructure-based design of molecules,processes, and flowsheets

The key to many chemical and energy conversion processes is the choice of the right molecule, for example, used as working fluid. However, the choice of the molecule is inherently coupled to the choice of the right process flowsheet. In this work, we integrate superstructure-based flowsheet design into the design of processes and molecules. The thermodynamic properties of the molecule are modeled by the PC-SAFT equation of state. Computer-aided molecular design enables considering the molecular structure as degree of freedom in the process optimization. To consider the process flowsheet as additional degree of freedom, a superstructure of the process is used. The method results in the optimal molecule, process, and flowsheet. We demonstrate the method for the design of an organic Rankine cycle considering flowsheet options for regeneration, reheating, and turbine bleeding. The presented method provides a user-friendly tool to solve the integrated design problem of processes, molecules, and process flowsheets.     

Photocatalytic Synthesis of p-Anisaldehyde in a Mini Slurry-Bubble Reactor under Solar Light Irradiation

Dense photocatalyst slurry was employed for the synthesis of p-anisaldehyde under solar light irradiation. An Fe-modified rutile TiO ₂ (Fe-TiO _2, 34.5 m ²/g) photocatalyst was used as a visible-light-responsive photocatalyst. A conventional TiO ₂ (P25, 35 m ²/g) photocatalyst was also examined as a reference catalyst. XRD patterns and diffuse reflectance spectra showed that Fe-TiO ₂ consists of 100 % rutile phase and absorbs more visible light compared to P25, respectively. The catalyst powder was suspended in an ethyl acetate solution of p-methoxytoluene in the mini-reactor, with oxygen bubbling, under a solar simulator, visible light, and UV LEDs. p-anisaldehyde, as a reaction product, was analyzed by sampling using gas-chromatograph. Regardless of the light source, Fe-TiO ₂ always outperformed P25 in terms of both generation rates (GR) of p-anisaldehyde and energy requirements (ER). It was demonstrated that the highly dense Fe-TiO ₂ slurry was efficient for the synthesis under solar light owing to the small size of the reactor. The small amount of Pt and ZrO ₂ cocatalysts significantly enhanced the GR under solar light. By adopting a visible light responsive Fe-TiO ₂ photocatalyst, the mini slurry-bubble reactor under solar light achieved a high GR per catalyst mass (CM), which is one to two orders higher than that reported by most previous studies with high-power lamps.