Isolation and Functional Characterization of a Salt-Responsive Calmodulin-Like Gene MpCML40 from Semi-Mangrove Millettia pinnata

Salt stress is a major increasing threat to global agriculture. Pongamia (Millettia pinnata), a semi-mangrove, is a good model to study the molecular mechanism of plant adaptation to the saline environment. Calcium signaling pathways play critical roles in the model plants such as Arabidopsis in responding to salt stress, but little is known about their function in Pongamia. Here, we have isolated and characterized a salt-responsive MpCML40, a calmodulin-like (CML) gene from Pongamia. MpCML40 protein has 140 amino acids and is homologous with Arabidopsis AtCML40. MpCML40 contains four EF-hand motifs and a bipartite NLS (Nuclear Localization Signal) and localizes both at the plasma membrane and in the nucleus. MpCML40 was highly induced after salt treatment, especially in Pongamia roots. Heterologous expression of MpCML40 in yeast cells improved their salt tolerance. The 35S::MpCML40 transgenic Arabidopsis highly enhanced seed germination rate and root length under salt and osmotic stresses. The transgenic plants had a higher level of proline and a lower level of MDA (malondialdehyde) under normal and stress conditions, which suggested that heterologous expression of MpCML40 contributed to proline accumulation to improve salt tolerance and protect plants from the ROS (reactive oxygen species) destructive effects. Furthermore, we did not observe any measurable discrepancies in the development and growth between the transgenic plants and wild-type plants under normal growth conditions. Our results suggest that MpCML40 is an important positive regulator in response to salt stress and of potential application in producing salt-tolerant crops.     

2010年至2019年中国国家自然科学基金资助中国盐湖研究项目分析

国家自然科学基金对学科发展具有扶持、引导作用, 其资助情况能反映出学科发展态势、研究前沿和热点。以2010—2019年国家自然科学基金对盐湖研究的资助项目数据为分析对象, 利用EXCEL、R Studio、VOSviewer等软件对资助年度、资助金额、依托单位、资助类别、项目名称、关键词等内容进行统计分析, 揭示了国家自然科学基金对盐湖基础研究的资助力度、趋势、研究团队分布, 发现当前盐湖热点研究方向包括盐湖相化学与溶液化学、盐湖资源分离与利用技术、盐湖资源综合利用技术、盐湖成盐规律与机制、盐湖锂资源利用技术、盐湖化学性质研究。     

医药副产含磷废盐的提纯研究

随着精细化工及中间体产品的发展,各类副产废盐量不断增加,由于其产生量大及难处理等特点,成为阻碍行业发展的一大瓶颈。主要开展了医药副产含磷废盐的提纯实验研究,针对废盐产生的途径和特性,采用洗脱剂（甲醇-乙醇）+活性炭混合洗脱与重结晶的方式,分别去除废盐中的有机物和氯化钠,回收可利用的磷酸盐,实现废盐的提纯资源化。当洗脱剂与废盐的体积质量比为1 mL/g、洗脱剂甲醇与乙醇的体积比为4∶6、活性炭用量为废盐质量的0.4%时,废盐中的有机物得到了有效去除。随后对得到的混盐进行重结晶得到回收磷酸盐,回收磷酸盐的纯度可达98%以上,符合工业磷酸盐行业标准的要求。将含磷废盐提纯回收磷酸盐,1 t废盐的处理成本约为174.24元,可回收0.61 t磷酸盐,实现了废盐的资源化再利用。     

Stability of protective oxide films in waste incineration environment—solubility measurement of oxides in molten chlorides

Solubility measurements of several oxides in molten NaCl-KCl and NaCl-KCl-Na₂SO₄-K₂SO₄ were conducted in three different levels of basicity. The dissolution behavior of the oxides showed almost the same tendency as that shown by the dissolution behavior of the oxides in molten Na₂SO₄ in literature. In a waste incineration environment, a protective Cr₂O₃ film easily dissolves in molten chlorides as CrO₄²⁻ because pO²⁻ of the molten chlorides tends to have a small value due to the effect of water vapor contained in the combustion gas. From the result of the solubility measurement, the addition of molybdenum and/or silicon was expected to improve the corrosion resistance of alloys. Laboratory corrosion tests confirmed this expectation. However, the scale analysis suggested that the effect of molybdenum could not be explained completely by only the mechanism derived from the result of the solubility measurement.     

An electrochemical method for the preparation of Mg–Li alloys at low temperature molten salt system

Mg–Li alloys have been prepared by electrolysis in a molten salt electrolyte of 50% LiCl–50% KCl (mass%) at low temperature of 420–510 °C. The effects of electrolytic temperature and cathodic current density on alloy formation rate and current efficiency were studied. For the deposition of metallic lithium on the cathode consisting of solid Mg and liquid Mg–Li, both electrolytic temperature and cathodic current density have no obvious influence on current efficiency; while for the deposition of metallic lithium on the solid magnesium cathode, both electrolytic temperature and cathodic current density greatly affect alloy formation rate and current efficiency. The optimum electrolysis condition is—molten salt mixture, LiCl:KCl = 1:1 (mass%), electrolytic temperature: 480 °C, cathode current density: 1.13 A cm⁻². Mg–Li alloys with low lithium content (about 25 wt% Li) were prepared via electrolysis at low temperature following by thermal treatment at higher temperature.     

Intelligent optimal control for lead-zinc sintering process state

The intelligent integrated predictive model of synthetical permeability was established using the fuzzy classifier to combine the time sequence predictive model with the craftwork parameter predictive model. Then, the estimation model of bum-through point（BTP） based on pipe stress point（PSP） method and the predictive model of BTP were proposed. The optimal control of permeability and heat states was implemented by using the fuzzy expert controller with self-studying mechanism. The application of the intelligent control technique suppresses 17% of the fluctuation of synthetical permeability and 12% of the fluctuation of BTP, stabilizes the output and quality of sinter and settles the basis for the optimization of output and quality of sintering process.     

含B4C中性盐浴渗硼工艺问题的研究

在含Ｂ４Ｃ中性盐浴渗硼的高温反应研究的基础上，对该盐浴存在的工艺问题进行了分析研究。指出了渗硼能力均匀性，工件表面腐蚀斑与玻璃体的关系，分析了老化盐致使工件清洗困难的成因。     

磁性纤维随机混合媒质等效电磁参数的计算

为计及强散射偶极子间的相互作用,引入参量εh和μh,利用广义多重散射理论及MATLAB计算机软件对在2 GHz～18 GHz频率下的体积占空比为8%的铁纤维随机混合媒质等效磁导率的实验值进行曲线的拟合,导出了耦合系数εh和μh,并在此基础上,对体积占空比分别为30%和20%的铁纤维随机混合媒质等效磁导率进行了计算,计算结果与实验吻合良好.     

钢铁构件表面上的无机富锌涂层

阐述了无机富锌涂层的研究、发展、特性和应用，指出无机富锌涂层具有杰出的耐环境侵蚀性能、耐化学性、耐溶剂性、耐辐射性、耐热性，在恶劣腐蚀环境下它是钢结构件的最佳底涂层。     

模具盐浴稀土钒硼共渗的组织与性能

研究了Ｃｒ１２Ｍｏｖ．Ｃｒ１２，９ＣｒＳｉ和Ｔ８等钢的盐浴稀土钒硼共渗共艺，渗层组织与性能；讨论了共渗工艺参数、共渗剂成分配比及稀土元素添加量等因素对共渗层的影响。冷作模具的使用寿命经ＲＥ－Ｖ－Ｂ共渗处理后比常规工艺处理的提高３～７倍。