单核细胞/高密度脂蛋白比值及钙/镁比值与维持性血液透析患者血管钙化的相关性分析

目的分析单核细胞/高密度脂蛋白比值(MHR)、钙/镁比值与维持性血液透析(MHD)患者血管钙化(VC)的相关性。方法选取2019年1月—2020年1月于三明市第二医院行MHD治疗的患者(透析龄1年以上)100例,根据腹部立位片结果分成非钙化组(28例)与钙化组(72例),比较2组性别、年龄、透析龄、血压、血红蛋白、清蛋白、血脂(三酰甘油、总胆固醇、低密度脂蛋白、高密度脂蛋白)、血糖、尿酸、血镁、血磷、血钙、单核细胞计数、甲状旁腺激素(iPTH)、MHR、钙/镁比值、血清成纤维细胞生长因子23(FGF-23)、25-羟维生素D。根据腹主动脉钙化评分(AACS)将钙化组患者分成轻度钙化组(16例)、中度钙化组(38例)、重度钙化组(18例),比较3组患者间MHR、钙/镁比值的差异,分析其与VC的相关性。结果非钙化组患者透析龄、血磷、血钙、单核细胞计数、iPTH、MHR、钙/镁比值、FGF-23低于钙化组,非钙化组血红蛋白、清蛋白、血镁、25-羟维生素D高于钙化组(P<0.05)。中度钙化组、重度钙化组MHR、钙/镁比值高于轻度钙化组,重度钙化组MHR、钙/镁比值也高于中度钙化组(P<0.05)。Pearson相关分析结果显示,AACS与年龄、透析龄、血磷、单核细胞计数、iPTH、MHR、钙/镁比值、FGF-23呈正相关(均P<0.05),与血镁、25-羟维生素D呈负相关(均P<0.05)。多因素Logistic回归分析结果显示,透析龄、血磷、iPTH、MHR、钙/镁比值、FGF-23水平为发生VC的危险因素(P<0.05),而血镁、25-羟维生素D为发生VC的保护因素(P<0.05)。结论MHD患者MHR、钙/镁比值与VC严重程度相关,其可用于预测VC发生的风险。

丙烯酸钙/镁对水泥水化进程的影响

研究了不同丙烯酸钙/镁配比及掺量、引发剂、促进剂、交联剂掺量对水泥水化进程的影响。通过进行标准稠度需水量、凝结时间、抗压强度测试,找出其对水泥水化进程的规律;利用XRD、水化热、DSC-TG等测试手段分析不同配比及掺量下的丙烯酸钙/镁对水泥水化物相组成的影响。研究结果表明:随着不同配比下的丙烯酸钙/镁掺量的增加,水泥标准稠度需水量是增加的,当掺量较低时,相同掺量的不同配比下丙烯酸钙/镁的标准稠度有一定的差异,但当掺量超过2.5%时,配比对标准稠度需水量的影响不是主要的;丙烯酸钙/镁降低水泥早期强度,但对水泥的后期强度发展有利。由水化热分析出改性水泥试样的放热速率低于空白水泥试样。

治疗心脑血管疾病中成药中钙镁比值的含量分析

为探讨中成药Ca Mg与治疗心脑血管疾病的关系 ,将 2 0种治疗心血管疾病中成药分为两组 ,一组为治疗心血管疾病药物 ,另一组为治疗脑血管疾病药物 ,采用火焰原子吸收分光光度法测定了钙镁含量 ,并计算钙 镁比值 ,分析其比值差异。结果表明 ,各种药物中Ca Mg比值有较大差异 ,治疗心血管疾病药物中Ca Mg平均值为 3 65 ,而治疗脑血管疾病药物中Ca Mg平均值为1 39,统计学检验 ,两者具有显著性差异 (P <0 0 5 )。

饮用淡化海水对大鼠血中铜锌钙镁铁的影响

目的通过对淡化海水卫生学指标进行检测分析及饮用淡化海水大鼠血中铜、锌、钙、镁、铁含量的测定,评价饮用淡化海水对大鼠血中铜、锌、钙、镁、铁的影响。方法首先对所采集的淡化海水的感官性状及一般化学指标20项、73项毒理学指标进行分析,判定其是否符合《生活饮用水卫生标准》（GB 5749-2006）。然后将采集所得淡化海水喂饲大鼠,与饮用市政自来水组大鼠进行对照比较,研究其血中铜、锌、钙、镁、铁含量,并计算铜锌比值、钙镁比值,分析饮用淡化海水对血中这些重要金属元素的影响。结果所采集的受试淡化海水感官性状和一般化学指标均合格,色度〈5,p H=6.94,呈现弱酸性。水中溶解性总固体浓度为186 mg/L,总硬度为13 mg/L,符合饮用水卫生标准要求。硼含量为1.3 mg/L高于限值（≤0.5 mg/L）,氟化物0.02 mg/L低于限值（≤1 mg/L）,其他指标均未检出。饮用淡化海水180 d,大鼠血中铜含量明显高于饮用市政自来水组（F=3.02,P=0.042）,其铜/锌也高于饮用市政自来水组（F=4.774,P=0.035）。饮用淡化海水90 d大鼠血中钙含量高于饮用市政自来水组大鼠（F=55.642,P=0.00）,其钙/镁也高于饮用市政自来水组大鼠（F=44.933,P=0.00）;饮用淡化海水180 d的大鼠血中镁、铁含量低于饮用市政自来水组大鼠（F=19.847,P=0.0007;F=5.309,P=0.027）。饮用淡化海水180 d大鼠血中钙/镁也高于饮用市政自来水组大鼠（F=5.309.P=0.030）。结论饮用淡化海水180 d会引起大鼠血中铜含量及铜/锌升高及血铁含量下降;饮用淡化海水90~180 d均会引起大鼠血中钙/镁升高。

二次铝灰烧结制备钙铝黄长石/镁铝尖晶石复相材料

以再生铝行业二次铝灰为主要原料,开展二次铝灰烧结制备钙铝黄长石/镁铝尖晶石复相材料的研究。热力学计算表明,二次铝灰添加氧化钙和氧化镁,理论上可以制备出钙铝黄长石/镁铝尖晶石复相材料。结果表明,当二次铝灰、氧化钙和氧化镁质量分数依次为70.80%、18.58%和10.62%,在1100~1500℃范围内,均能制备出钙铝黄长石/镁铝尖晶石复相材料;随烧结温度升高,钙铝黄长石/镁铝尖晶石复相材料纯度和结晶度明显提高,抗压强度呈升高趋势,显气孔率呈下降趋势。当烧结温度为1500℃时,所制备出钙铝黄长石/镁铝尖晶石复相材料显气孔率和抗压强度分别为33.87%和40.18 MPa。

漆酶-Ca^(2+)/Mg^(2+)双诱导乳液凝胶的构建及油-水双相负载功能因子的应用

为进一步优化乳液凝胶的制备工艺,本研究利用漆酶与钙/镁离子双诱导的方式构建大豆分离蛋白-甜菜果胶乳液凝胶,根据归一化的方法得到凝胶质构特性综合值的计算模型,并提出一种利用较低浓度镁离子替换高浓度钙离子的方案,以此降低凝胶制备过程中离子的添加量。结果表明,对比漆酶与钙离子双诱导乳液凝胶,漆酶与镁离子双诱导乳液凝胶具有更短的凝胶时间(340 s)和相似的流变特性,更均匀的微观结构及油滴分布,更佳的贮藏稳定及在小肠中更高的释放率(β-胡萝卜素释放率73.1%,核黄素释放率85.7%)。本研究构建了一种新型的乳液凝胶体系并应用于油-水双相负载递送功能因子领域,同时验证了利用较低浓度镁离子诱导成胶的可行性。

帘线钢中夹杂物控制技术的研究进展

钢中大尺寸、高熔点、不易变形的脆性夹杂物以及酸溶铝,极易引起帘线钢在拉拔、合股过程中出现断丝现象。因此,夹杂物的研究与控制对提高帘线钢品质来说至关重要。将夹杂物控制在低熔点区域,提高其塑性是目前的研究热点。本文概述了帘线钢国内外生产工艺情况,阐述了帘线钢中夹杂物可塑性研究状况。总结了钙/镁变性、稀土变性以及严格控制钢中酸溶铝含量等方法,以期对夹杂物的控制有所借鉴。

Separation of manganese from calcium and magnesium in sulfate solutions via carbonate precipitation

The separation of manganese from sulfate solutions containing 14.59 g/L Mn2+, 1.89 g/L Mg2+ and 1.54 g/L Ca2+ was preformed successfully by carbonate precipitation. The results of thermodynamic analysis and tests indicate that carbonate precipitation holds better selectivity for manganese over magnesium than hydroxide precipitation and the feeding method is the most critical factor for minimizing the co-precipitation of calcium and magnesium. Furthermore, with adding MnSO4 solution to NH4HCO3 solution, the effects of the initial NH4HCO3 concentration, NH4HCO3 amount, solution pH value, reaction temperature and time on carbonate precipitation were evaluated and the optimum precipitation conditions were obtained. Under the optimum conditions, the precipitation rates of Mn2+, Ca2+ and Mg2+ are 99.75%, 5.62% and 1.43%, respectively. Moreover, the prepared manganese carbonate was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX). The results demonstrate that the product can be indexed to the rhombohedral structure of MnCO3.

Leaching kinetics of low-grade copper ore containing calcium-magnesium carbonate in ammonia-ammonium sulfate solution with persulfate

The leaching kinetics of copper from low-grade copper ore was investigated in ammonia-ammonium sulfate solution with sodium persulfate. The effect parameters of stirring speed, temperature, particle size, concentrations of ammonia, ammonium sulfate and sodium persulfate were determined. The results show that the leaching rate is nearly independent of agitation above 300 r/min and increases with the increase of temperature, concentrations of ammonia, ammonium sulfate and sodium persulfate. The EDS analysis and phase quantitative analysis of the residues indicate that bornite can be dissolved by persulfate oxidization. The leaching kinetics with activation energy of 22.91 kJ/mol was analyzed by using a new shrinking core model （SCM） in which both the interfacial transfer and diffusion across the product layer affect the leaching rate. A semi-empirical rate equation was obtained to describe the leaching process and the empirical reaction orders with respect to the concentrations of ammonia, ammonium sulfate and sodium persulfate are 0.5, 1.2 and 0.5, respectively.

Microstructure and tensile properties of AE42-based magnesium alloys with calcium addition

The as-cast microstructure of AE42 was of typical dendritic and composed of the a matrix and some needle-shaped interphases Al11RE3. A small mount of Ca addition results in significant microstructural refinement and formation of a Al2Ca phase, which showed two kinds of morphologies, lamellar and tiny granular. The former distributes on grain boundaries and the later is within the matrix grains. With the increase of Ca addition the volume fraction of Al-RE compound (Al11RE3) decreases, but Al2Ca increases. Addition of Ca causes a significant increase of yield strength of the alloy both at ambient and elevated temperatures, but a little decrease of the ductility. With calcium addition the ultimate strength decreases at ambient temperature and 150°t, but increases at 175°C and 200°C.

Removal of magnesium and calcium from electric furnace titanium slag by H_3PO_4 oxidation roasting-leaching process

H3PO4 oxidation roasting followed by HCl acid leaching was proposed to remove magnesium and calcium from electric furnace titanium slag containing 3.12% MgO and 0.86% CaO. XRF, XRD and SEM techniques were used to characterize the composition, mineral phase component and microstructure of the titanium slag. The H3PO4 oxidation thermodynamic, mineral phase transformation, microstructure, element distribution in titanium slag during H3PO4 oxidation process and leaching process were investigated. The thermodynamic analysis indicated that H3PO4 could promote the decomposition of MgTi2O5 and CaSiO3. The results indicated that H3PO4 could effectively promote the transformation of titanium-bearing mineral to rutile and enrich the impurities in MxTi（3-x）O5 into phosphate which could be removed by acid leaching process. Under the studied conditions, the leaching rates of magnesium and calcium reached 94.68% and 87.19%, respectively. The acid leached slag containing 0.19% MgO and 0.13% CaO（mass fraction） was obtained.

Effects of FCMP Compound Fertilizer on Development and Yield of Early Rice

[Objective] The aim was to explore effects of FCMP compound fertilizer on growth, development and yield of early rice. [Method] Based on lower-graded phos- phate resource, effects of FCMP compound fertilizers on yield and growth of early rice in a field were researched. [Result] FCMP compound fertilizers 0, 1 and 2 en- hanced rice yield, increasing by 21.86%, 20.25% and 13.46%, compared with the rice applied with conventional fertilizer; number of productive ears and grain number per ear in unit area were improved by FCMP compound fertilizer, for example, the two factors achieved the highest with FCMP compound fertilizer 1, increasing by 11.70% and 19.63%. Furthermore, FCMP compound fertilizer promoted plant height and tiller number, maintained high photosynthetic efficiency, enhanced lodging-resis- tance and guaranteed stable and high yield. [Conclusion] The research is of theoret- ical and practical significance for further exploration of production techniques and application of FCMP compound fertilizer.

Effects of Oral Administration of Propylene Glycol and Ca-P-Mg Mixture on Milk Quality and SCC of Dairy Cows after Birth

In order to further study the postpartum care technology of dairy cows,the effects of oral administration of propylene glycol or Ca-P-Mg mixture and compound oral rehydration salts on milk quality and SCC of dairy cows after birth were investigated. The results showed that the milk fat and dry matter contents in the dairy cows administered with Ca-P-Mg mixture and compound oral rehydration salts were higher than those in the dairy cows administered with propylene glycol（P 〈0.05）. However, there were no significant differences in milk sugar and protein contents and SCC between the two administration groups.

Influence of solution temperature on corrosion resistance of Zn-Ca phosphate conversion coating on biomedical Mg-Li-Ca alloys

The influence of phosphating bath at different temperatures on the formation and corrosion property of calcium-modified zinc phosphate conversion coating （Zn-Ca-P coating） on Mg-Li-Ca alloy was investigated. The morphologies, elemental distribution and chemical structures of the coatings were examined via SEM, EPMA, EDS, XRD and FT-IR. The corrosion resistance was assessed by hydrogen evolution, potentiodynamic polarization and EIS. The results show that the coating is composed of single element Zn and ZnO at below 45 ℃;whereas the coatings are predominantly characterized by Zn3（PO4）2·4H2O and small amount of element zinc and ZnO at above 50 ℃. Mg-Li-Ca alloy with Zn-Ca-P coatings prepared at 55 ℃ has the highest corrosion resistance. However, the hydrogen evolution rates of the coatings obtained at 40-50 ℃ is accelerated due to the galvanic corrosion between the imperfection of the single element Zn coating and the Mg substrate.

Effects of Foliar Spraying of Magnesiumpotassium Sulfate Fertilizer on Absorption of Magnesium, Potassium and Calcium in Differentposition Tobacco Leaves

[Objective] ln the Mg-deficient （exchangeable Ca/Mg ratio ＆gt; 20） tobacco-growing areas in Qujing City of Yunnan Province, the ratio of Ca/Mg was adjusted by applying Mg fertilizer in soil and spraying Mg fertilizer on tobacco leaves. ln ad-dition, the effects of Mg fertilization on the absorption of K, Ca and Mg in flue-cured tobacco leaves were investigated, providing theoretical basis and production guidance for the balanced fertilization technology in the Mg-deficient flue-cured to-bacco-growing areas in Qujing City of Yunnan Province. [Method] The field plot test and randomized complete block design were adopted in this research. The group without Mg fertilization was treated as control. There were 3 treatment groups for foliar spraying of magnesium-potassium sulfate fertilizer and 2 treatment groups for soil application ＋ foliar spraying of magnesium-potassium sulfate fertilizer. The tobac-co roots, stems, lower leaves, middle leaves and upper leaves were dried and weighed. They were grinded for the determination of K, Ca and Mg content. The total K, Ca and Mg content in upper （B2F）, middle （C3F） and lower （X2F） flue-cured tobacco leaves in each plot was measured. [Result] The foliar spraying and soil application ＋ foliar spraying al increased the absorption of Mg and K in middle and lower tobacco leaves and the absorption of Ca in lower tobacco leaves, but de-creased the absorption of Mg, K and Ca in upper leaves and the absorption of Ca in middle leaves. Among the positions, the accumulated distribution of Mg, K and Ca ranked as middle leaves ＆gt; lower leaves ＆gt; upper leaves. With the application of Mg fertilizer, the Ca/Mg ratio and K/Mg ratio al decreased in middle and upper to-bacco leaves; while the Ca/Mg ratio increased in the lower tobacco leaves, and the K/Mg ratio showed no significant difference among treatment groups. [Conclusion] The foliar spraying and soil application ＋ foliar spraying of magnesium-potassium sulfate fertilizer affected the Ca/Mg ratio and K/Mg ratio in tobacco leaves mainly through affecting the absorption of Mg.

Corrosion resistance of cerium-doped zinc calcium phosphate chemical conversion coatings on AZ31 magnesium alloy

Zinc calcium phosphate （Zn-Ca-P） coating and cerium-doped zinc calcium phosphate （Zn-Ca-Ce-P） coating were prepared on AZ31 magnesium alloy. The chemical compositions, morphologies and corrosion resistance of coatings were investigated through energy-dispersive X-ray spectroscopy （EDS）, X-ray photoelectron spectroscopy （XPS）, X-ray diffraction （XRD）, electron probe micro-analysis （EPMA） and scanning electron microscopy （SEM） together with hydrogen volumetric and electrochemical tests. The results indicate that both coatings predominately contain crystalline hopeite （Zn3（PO4）2·4H2O）, Mg3（PO4）2 and Ca3（PO4）2, and traces of non-crystalline MgF2 and CaF2. The Zn-Ca-Ce-P coating is more compact than the Zn-Ca-P coating due to the formation of CePO4, and displays better corrosion resistance than the Zn-Ca-P coating. Both coatings protect the AZ31 Mg substrate only during an initial immersion period. The micro-galvanic corrosion between the coatings and their substrates leads to an increase of hydrogen evolution rate （HER） with extending the immersion time. The addition of Ce promotes the homogenous distribution of Ca and formation of hopeite. The Zn-Ca-Ce-P coating has the potential for the primer coating on magnesium alloys.

Elastic Tensor and Thermodynamic Property of Magnesium Silicate Perovskite from First-principles Calculations

The thermodynamic and elastic properties of magnesium silicate （MgSiO3） perovskite at high pressure are investigated with the quasi-harmonic Debye model and the first-principles method based on the density functional theory. The obtained equation of state is consistent with the available experimental data. The heat capacity and the thermal expansion coefficient agree with the observed values and other calculations at high pressures and temperatures. The elastic constants are calculated using the finite strain method. A complete elastic tensor of MgSiO3 perovskite is determined in the wide pressure range. The geologically important quantities： Young＇s modulus, Poisson＇s ratio, Debye temperature, and crystal anisotropy, are derived from the calculated data.

Microstructure and properties of biodegradable β-TCP reinforced Mg-Zn-Zr composites

Magnesium alloys have good biocompatibility, but their mechanical properties and corrosion resistance may not be satisfied for using as degradable materials within bone due to its high corrosion rate in the physiological environment. Nano β-TCP particles were added into Mg-Zn-Zr alloy to improve its microstructure and the properties. As-extruded Mg-3Zn-0.8Zr alloy and Mg-3Zn-0.8Zr/xβ-TCP （x=0.5%, 1.0% and 1.5%） composites were respectively fabricated. The grains of Mg-Zn-Zr/β-TCP composites were significantly refined. The results of the tensile tests indicate that the ultimate tensile strength and the elongation of composites were improved with the addition of β-TCP. The electrochemical test result in simulation body fluid shows that the corrosion resistance of the composites was strongly enhanced comparing with that of the alloy. The corrosion potential of Mg-3Zn0.8-Zr/1.0β-TCP composite is 1.547 V and its corrosion current density is 1.20×10 6 A/cm 2 .

Recovery of cobalt and nickel in the presence of magnesium and calcium from sulfate solutions by Versatic 10 and mixtures of Versatic 10 and Cyanex 301

The extraction and stripping characteristics of Versatic 10 and its mixtures with Cyanex 301 were investigated for the recovery of cobalt and nickel from sulfate solutions containing magnesium and calcium. The optimum extraction factors of Versatic 10 were initial pH of 2.5, O/A ratio of 1/3, and saponification rate of 60%. The loaded Versatic 10 was stripped by using 2 mol/L H2SO4 at O/A ratio of 1/1. The optimum volume ratio of Versatic 10 to Cyanex301 was 7/3 in the mixtures, which could effectively reduce the equilibrium pH to 3.50. And the loaded mixtures were stripped by using 2 mol/L H2SO4at O/A ratio of 1/2. The reaction principle of Versatic10 and metal ions is an ion exchange reaction. However, in the extraction reaction of and metal ions, besides the ion exchange reaction, the strong coordination effect between Cyanex 301 and metal ions also exists, which is much weakened in the extraction reaction of the mixtures and metal ions.

Pedogenic and Anthropogenic Influence on Calcium and Magnesium Behaviors in Stagnic Anthrosols

The formation of Stagnic Anthrosols is closely related to rice planting and parent materials. Six representative pedons, two from each of three Stagnic Anthrosol subgroups, Vertic Haplic-, Vertic Gleyic-, and Sulfic Gleyic-Stagnic Anthrosols, from different parent materials and soil formation processes, from Liaoning Province, China, were selected and used along with additional supporting data to assess the potential impact in each soil subgroup combination of both pedogenic and anthropogenic factors on the migration and geochemical characteristics of calcium (Ca) and magnesium (Mg) and their relations to soil particle-size composition. Results revealed that exchangeable Mg was correlated positively with clay and silt content, but negatively with sand content, suggesting that clay and silt could retain more exchangeable Mg than sand. Also, in the six pedons exchangeable Ca/Mg ratios generally decreased with depth, which was most likely due to the preferential retention of Mg below the Apl horizon and the effects of bio-cycling in rice-soil systems. The pedons with high pH had smaller exchangeable Ca/Mg ratios than those with low pH. Thus, it was concluded that exchangeable Ca/Mg ratios could be helpful in classification of Stagnic Anthrosols.