Genetic Variation of Maize Hybrids in Grain Yield Response to Potassium and Inhibiting Nitrification

Nine maize hybrids were grown under five N levels with or without a nitrification inhibitor (nitrapyrin or an experimental inhibitor, XDE474) to evaluate the effect of inhibiting nitrification on grain yield performance and cannibalisation of nutrients from vegetative tissues during kernel maturation. Grain yield response of these hybrids also was evaluated under a paired combination of four N levels and two K levels. Hybrids responded differently to N, the form of N, and K treatments, and there appeared to be a genetic basis for preference of the form of N (ammonium versus nitrate nitrition). Crosses that involved the Mo17 family responded positively to inhibiting nitrification which provided a larger portion of the N in the ammonium form, but incorporation of early maturing genes reduced the positive response to ammonium nutrition. Like ammonium nutrition, maize hybrids showed a differential response to K treatments, and the availability of a large amount of K early in the growing season produced a negative effect on grain yield. The experimental nitrification inhibitor, XDE474, was more effective than nitrapyrin in increasing grain yield and minimising cannibalisation of nutrients in the leaf tissue.     

钙镁复合药剂处理洗煤废水的效果及作用机理研究

用CaCl2与MgS04复配出新的复合药剂,通过试验确定了适宜m(CaCl2):m(MgSO4)=1:1.采用正交实验确定了钙镁复合药剂与PAM联用处理洗煤废水的最佳组合条件,并通过生产性试验验证了实验室的试验结果.分析认为钙镁复合药剂对洗煤废水的混凝机理并不完全符合DLVO理论,它是多方面因素共同作用的结果.     

铝电解质中的钾脱除技术

针对我国西南地区铝电解质中钾含量偏高的问题,提出了铝电解工序钾脱除技术方案。根据某电解铝企业的实际情况,通过取样分析、理论推导,以及浮选分离试验,提出了具体的实施方案,并论证了方案的可行性。研究结果表明：电解质中的KF易挥发并以KAlF4和K2NaAl3F12、K2NaAlF6等固体氟铝酸盐的形态进入铝电解烟气;不同企业的铝电解质中KF含量不同,但电解槽挥发物中KF含量却比较接近;采用收集装置将铝电解烟气中的固体挥发物收集走,使其不再混入载氟氧化铝进入电解槽中,可快速降低铝电解槽中KF的平衡浓度;固体挥发物通过浮选可分离其中的氧化铝和氟铝酸盐,氟铝酸盐可用于制备低温电解质。该方案在技术上具有可行性。     

不同晶须改性聚丙烯的性能研究

研究了碱式硫酸镁(M-HOS)和钛酸钾(K2Ti6O13)晶须填充改性PP热变形温度、流动性能和力学性能等。结果表明,这两种晶须均能有效地提高PP热变形温度,同时也能改善其力学性能。镁盐和钛酸钾晶须的最佳含量均为30%,此时PP热变形温度分别提高到151.8℃和146.5℃。     

硝酸钾真空冷却结晶工艺

介绍了真空冷却结晶技术应用于硝酸钾生产的工艺原理与过程。确定了硝酸钾溶液真空冷却结晶操作条件为,真空度2 339 Pa,结晶时间2.0 h,冷却终点温度30℃。真空冷却结晶比传统的夹套与蛇管冷却结晶具有显著优势,需要的冷却水量大幅度减小,冷却速度快,冷却均匀,干净卫生,是现代结晶技术发展方向之一。     

高锰酸钾复合药剂对水中邻氯酚去除效能的研究

本文以水中的邻氯苯酚为研究对象,在实验基础上,考察了高锰酸钾及高锰酸钾复合药剂对纯水中微量邻氯酚的去除效果,用可见分光光度计分析,对二者的除酚效果进行了对比。结果表明:高锰酸钾复合药剂对水中微量邻氯酚具有较好的去除能力。同时还考察了水样pH值,高锰酸钾及其复合药剂投加量,反应水温,反应时间等因素对邻氯酚去除效果的影响。     

微波辐射对硫酸钙结晶生长的影响

在相同的结晶条件下,采用微波加热与传统加热所形成的硫酸钙晶体形貌有明显差异。通过蒙特卡罗模拟对此现象进行了分析和解释,模拟结果显示,微波辐射影响了硫酸钙晶体的生长过程,从而影响了硫酸钙晶体形貌。     

滦河水的除藻实验研究

该文针对滦河源水进行了杀藻的试验研究。研究结果表明：对引滦水而言,硫酸铜、高锰酸钾和过氧化氢三种杀藻剂的藻类去除率均随药剂投量的增加而升高;在原水含藻量较高（高于1000万个／L）情况下,硫酸铜较佳投量1．0mg／L,藻类去除率为70％～80％;过氧化氢投量4mg／L,藻类去除率为60％左右;高锰酸钾投量0．6mg/L,藻类去除率为85％;通过杀藻效果、经济性以及安全性等方面的综合比较,对于以有毒蓝藻为优势藻的引滦水,三种杀藻剂的优劣排序为：高锰酸钾〉硫酸铜〉过氧化氢。     

Interfacial potassium induced enhanced Raman spectroscopy for single-crystal TiO2 nanowhisker

Structural control and element doping are two popular strategies to produce semiconductors with surface enhanced Raman spectroscopy(SERS) properties. For TiO_2 based SERS substrates, maintaining a good crystallinity is critical to achieve excellent Raman scattering. At elevated temperatures(N600 °C), the phase transition from anatase to rutile TiO_2 could result in a poor SERS performance. In this work, we report the successful synthesis of TiO_2 nanowhiskers with excellent SERS properties. The enhancement factor, an index of SERS performance, is 4.96 × 10~6 for methylene blue molecule detecting, with a detection sensitivity around 10~(-7) mol·L~(-1).Characterizations, such as XRD, Raman, TEM, UV–vis and Zeta potential measurement, have been performed to decrypt structural and chemical characteristics of the newly synthesized TiO_2 nanowhiskers. The photo absorption onset of MB adsorbed TiO_2 nanowhiskers was similar to that of bare TiO_2 nanowhiskers. In addition, no new band was observed from the UV–vis of MB modified TiO_2 nanowhiskers. Both results suggest that the high enhancement factor cannot be explained by the charge-transfer mechanism. With the support of ab initio density functional theory calculations, we reveal that interfacial potassium is critical to maintain thermal stability of the anatase phase up to 900 °C. In addition, the deposition of potassium results in a negatively charged TiO_2 nanowhisker surface, which favors specific adsorption of methylene blue molecules and significantly improves SERS performance via the electrostatic adsorption effect.     

Assessment on the mechanical,structural, and thermal attributes of green graphene-based water soluble polymer electrolyte composites

In the current study, graphene oxide (GO) was prepared using green chemistry with modified Hummer's method without incorporating sodium nitrate (NaNO₃). Solvent casting was employed to fabricate GO-doped poly(ethylene oxide) (PEO), that is, PEO/GO composites with various proportion of Na₂SO₄ and were then subjected to characterization via advanced spectroscopic techniques for different physicochemical aspects to estimate their potential applications as marketable products. XRD analysis explored that fabricated composites are more crystalline than neat PEO. PEO/GO/Na₂SO₄ composite films offered maximum crystallinity. SEM displayed the same trend. TG/DTA thermogram exposed better thermal stability than pristine polymer. FTIR studies confirmed complexation among hybrid's components. Elongation-at-break and Young's modulus displayed an enhancing behavior with an incremental loading of salt and filler. In terms of mechanical performance, composite of PEO with 0.37 wt % GO and 0.08 g salt was found to be an ideal composition during the course of study. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48376.