Dry Mix Slag—High-Calcium Fly Ash Binder. Part Two: Durability

This work investigates durability of cement-free mortars with a binder comprised of ground granulated blast furnace slag (GGBFS) activated by high-calcium fly ash (HCFA) and sodium carbonate (Na2CO3): the soundness, sulfate resistance, alkali-silica reactivity and efflorescence factors are considered. Results of tests show that such mortars are resistant to alkali-silica expansion. Mortars are also sulfate-resistant when the amount of HCFA in the complex binder is within a limit of 10 wt%. The fineness of fly ash determines its’ ability to activate GGBFS hydration, and influence soundness of the binder, early strength development, sulfate resistance and efflorescence behavior. The present article is a continuation of authors’ work, previously published in MSA, Vol. 14, 240-254.

The role of intracellular sodium (Na+) in the regulation of calcium (Ca2+)-mediated signaling and toxicity

It is known that activated N-methyl-D-aspartate receptors (NMDARs) are a major route of ex-cessive calcium ion (Ca2+) entry in central neu-rons, which may activate degradative processes and thereby cause cell death. Therefore, NMD- ARs are now recognized to play a key role in the development of many diseases associated with injuries to the central nervous system (CNS). However, it remains a mystery how NMDAR ac-tivity is recruited in the cellular processes leading to excitotoxicity and how NMDAR activ-ity can be controlled at a physiological level. The sodium ion (Na+) is the major cation in ex-tracellular space. With its entry into the cell, Na+ can act as a critical intracellular second mes-senger that regulates many cellular functions. Recent data have shown that intracellular Na+ can be an important signaling factor underlying the up-regulation of NMDARs. While Ca2+ influx during the activation of NMDARs down-regu-lates NMDAR activity, Na+ influx provides an essential positive feedback mechanism to over- come Ca2+-induced inhibition and thereby po-tentiate both NMDAR activity and inward Ca2+ flow. Extensive investigations have been con-ducted to clarify mechanisms underlying Ca2+- mediated signaling. This review focuses on the roles of Na+ in the regulation of Ca2+-mediated NMDAR signaling and toxicity.

Barium, Calcium and Sodium, Cyanide, Phosphate and Sulphate Contents of Groundwater in Some Ika Communities of Delta State, Nigeria

Barium, calcium, sodium, cyanide, phosphate and sulphate and contents of groundwater in Boji-Boji (BB) area and suburbs of Ika land, Delta State, Nigeria were studied. Groundwater is the predominant source of water for inhabitants of these communities without any form of treatment. 55 borehole water sites spread within these five sample sub-areas. The metal ions were analyzed using Solar Unicam flame Atomic Absorption Spectrophotometer. Sulphate, phosphate, and cyanide contents were determined by colorimetric method. Results indicate the presence of sodium, calcium, sulphate, and phosphate. However, barium and cyanide were below detection limit. Secondly, there was a relatively higher proportion of calcium and sulphate than sodium and phosphate in its aquifer. Thirdly, a mean ratio value of 0.018 and 0.158 was observed for the ratios of Na+/Ca2+ and ?respectively. Fourthly, sodium showed good correlation with all the other parameters. Finally, nearly all the studied parameters have concentrations below the maximum contaminant levels of the World Health Organization (WHO), invariably inferring that the water is wholesome with respect to the analytes. However, concern still remains from a health point of view on the sodium concentrations in many sample areas.

Effects of Paper Mill Sludge on Potassium, Sodium, Calcium, and Magnesium Concentrations in Different Soybean Cultivars

A field experiment was conducted on a sandy loam soil at an Experimental Farm in Taejon, South Korea, to determine the effects of paper mill sludge compost application rates on K, Na, Ca and Mg concentrations of soybean (Glycine max(L.) Merr.) aboveground tissues and the genotypic effects on the concentrations of these elements. Sludge compost treatments of 0, 75, and 150 t ha-1 were applied to 30 diverse soybean cultivars. Concentrations of K, Na, Ca, and Mg in aboveground tissues harvested 69 days after planting (DAP) varied with the genotype and the application rate of paper-mill sludge compost, with the sludge compost application rate exerting stronger influence on these concentrations than the genotype. The magnitude of variation caused by both genotype and sludge compost application was in the order of Mg ＞ K ＞ Ca ＞ Na. Significantly positive correlations were observed between K and Na (P ＜ 0.01), Na and Ca(P ＜ 0.05), and Ca and Mg (P ＜ 0.01). Also, the lower the sludge compost application rate, the larger the variation in the concentrations of K, Na, and Ca. From this several cultivars were identified for use as an accumulator for one or more of these elements.

Hollow calcium carbonate microspheres prepared in the presence of polyoxyethylene(20) sorbitan monolaurate and sodium dodecyl sulfate

Hollow calcium carbonate （ CaCO3 ） microspheres were prepared in aqueous solution with the presence of polyoxyethylene （20） sorbitan monolaurate （ Tween20 ） and sodium dodecyl sulfate （SDS）. The microspheres were characterized with X-ray diffraction （XRD） , scanning electron microscopy （SEM） and transmission electron microscope （TEM）. The X-ray diffraction data showed that the hollow CaCO3 microsphere consisted of calcite crystals. The influence of Tween20 and SDS concentrations on the morphology of CaCO3 crystals was investigated. The results suggested that the ＂core-shell model＂ of Tween20/SDS micelle aggregated as templates, which could control the growth of hollow CaCO3 microspheres. The interaction between mixed surfactants and calcium ions played a critical role in organizing calcium carbonate in microscopic level.

Statistical Studies of the Physicochemical Analytic Results of a Series of Synthetic Calcium Hydroxyapatite Containing Carbonate and Sodium

The objective of this study is to present a simple method of statistical calculation that allowed us to determine the relationship between the different data obtained from the characterization of the synthetic carbonated apatites containing sodium, in order to find the fundamental substitution mechanism(s) for incorporation of Na+ and?CO32- and to establish the general formula. For that, a series of hydroxyapatites containing carbonate and sodium (Na-CO3HAps) has been obtained by the precipitation method. All the compounds were characterized by infrared spectra (IR), powder X-ray diffraction (PXRD) and elemental analysis. The statistical treatment of the experiment result allows us to determine the relationship between one variable and the change in the other and to found the fundamental substitution mechanism(s) for incorporation of Na+ and?CO32- . Analysis of variance (ANOVA) allows us to test the models proposed.

Effect of Compounding of Sodium Tripolyphosphate and Super Plasticizers on the Hydration of α-calcium Sulfate Hemihydrate

The inhibition and its mechanism of sodium tripolyphosphate （STP） composited with super plasticizers （SPs） on hydration of α-calcium sulfate hemihydrate were studied by setting time, strength, hydration heat, X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS）, electronic probe micro analysis （EPMA）, scanning electron microscopy （SEM） and differential scanning calorimeter （DSC） measurements. The experimental results show that compared with STP addition, compositing STP with polycarboxylate （PC） plasticizer, the final setting time is prolonged from 0.5h to 2hs. While formulating STP with naphthalene-based plasticizer （NAP） or sulfonate melamine formaldehyde plasticizer （SMF）, the final setting time is reduced to quarter of an hour. Similar changes can also be found in the rate of exothermic hydration and hydration degree. Formulating STP with suitable addition of PC can enhance the strength, while compositing STP and NAP or SMF weakens the strength. Besides, adding STP or STP and SMF, obvious movement （more than 1ev） of binding energy of Ca2p1/2 and Ca2p3/2 is detected. Compared with STP addition, content of the characteristic element （P） of STP is cut down form 1.1% to 0.49% by compositing STP with SMF. Furthermore, as hydration age increases, hydration inhibition in the presence of admixtures weakens and even disappears within 56 h.

Effect of an Anionic Surfactant on Hydraulic Conductivities of Sodium- and Calcium-Saturated Soils

The effect of sodium dodecylbenzenesulfonate (SDBS), an anionic surfactant used widely in household products and industrial processes, on saturated hydraulic conductivities (Ksat) of an Anthrosol saturated with sodium (Na-soil) or calcium (Ca-soil) was analyzed in a laboratory experiment using the constant head method, and adsorption and dispersion experiments were also conducted to infer the possible mechanisms of Ksat fluctuations. The results showed that SDBS was more intensely adsorbed in the Ca-soil than in the Na-soil. With an increase in the SDBS concentration, the stability of the Na-soil suspensions decreased when the SDBS concentration was less than 1.2 mmol L-1 and then above this concentration, increased markedly, while the stability of the Ca-soil suspensions increased gradually at all SDBS concentrations studied. With an increase in the SDBS concentration, the Ksat of the Na-soil increased, which resulted mainly from the increase of water channels in the soil because of the coagulation of the soil particles, while the Ksat of Ca-soil decreased mainly on account of the clogging of partial water channels by precipitated Ca(DBS)2 and the fine soil particles generated.

Thermodynamic analysis on sodium carbonate decomposition of calcium molybdenum

According to the principle of mass balances and thermodynamic data, lg [Me]—pH diagrams (Me=Ca, Mo) for Ca-Mo-CO3-H2O system at 25 ℃ were presented with total dissolved carbon-containing ions concentrations of 0.01 mol/L and 1 mol/L, and lg [Me]—pH diagram for Ca-Mo-H2O system at 25 ℃ was also depicted. The effects of system pH value and total dissolved carbon-containing ions concentrations on the concentrations of the species in Ca-Mo-CO3-H2O system were studied. The results show that the stability region of CaMoO4 reduces significantly in the presence of sodium carbonate. In order to achieve effective leaching of molybdenum from CaMoO4, a certain concentration of sodium carbonate is necessary. High total dissolved carbon-containing ions concentrations and high pH values facilitate to the leaching of CaMoO4 and dissolved sodium carbonate is an efficient leaching agent for decomposing CaMoO4.

Study of Calcium and Sodium Behavior to Identify Milk Adulteration Using Flame Atomic Absorption Spectrometry

A fast and direct method for determination of milk adulteration by monitoring of calcium and sodium concentrations variations was described. Milk samples were furnished by a dairy company located at S?o Carlos (S?o Paulo State, Brazil) and and spiked with tap-water, whey, hydrogen peroxide, synthetic urine, urea and synthetic milk in the ranged from 5% to 50% (v/v), expect for caustic soda. Caustic soda was added in the milk until establish the original pH. The milk samples were analyzed by using flame atomic absorption spectrometry (FAAS) and no acid digestion process was required. Results showed a significant decrease in the Na and Ca concentrations with addition of synthetic milk and tap-water, a nonlinear variation with addition of synthetic urine, whey and hydrogen peroxide and a largest increase in the Na concentration with addition of NaOH. Correlation between Na and Ca concentrations in pure and adulterated milk were evaluated by paired t-test at a 95% confidence level. Results showed that the method proposed is efficient to identify samples adulterated with tap-water, caustic soda, synthetics milk and urine.

Altered Erythrocyte Membrane Calcium Binding in Hypertensive Rats and the Effects of Sodium Tanshinone Ⅱ-A Sulphonate on It

The calcium binding of erythrocyte membrane was determined in spontaneous hypertensiverats (SHR)and renovascular hypertensive rats (RVHR two-kidney, one-clip model) and the effect ofsodium tanshinone Ⅱ-A sulfonate(DS-201)on the calcium binding in SHRs was investigated. Ourresults show that the basal calcium binding was reduced in SHRs (P<0.01 vs WKY),while the maximalcalcium binding was not,but both typies calcium bindings had no significant change in RVHRs.Sodiumtanshinone Ⅱ-A sulfonate (125μ mol/L)have no effect on the calcium binding of ecythrocyte membraneof SHR in vitro.These data further support the hypothesis that there is a cell membrane abnormalitypresent in SHRs which may possibly serve as a marker genetics of in hypertension.

A Study on the Mechanism Regulating Acetate to Propionate Ratio in Rumen Fermentation by Dietary Carbohydrate Type

The research direction of our team is nutrition and physiology of ruminants, including dietary nutrition metabolism and rumen microorganisms. Previous research has shown that ruminal acetate-to-propionate ratio is related to diet utilization efficiency. At present, it is believed that the main factors affecting the ruminal acetate-to-propionate ratio are the degradation rate of the diet and the rumen microbial structure, but the main mechanism is unclear. This study found that the effect of ruminal acetate-to-propionate ratio was not affected by the concentration of the fermentation substrate, but was affected by the structure of the rumen microbiota. We believe that changes in the rumen microflora structure are the main mechanism for regulating the ruminal acetate-to-propionate ratio. This will help people to further understand the rumen physiology, thereby gradually improving feed conversion efficiency and reducing production costs. Abstract: In order to explore the mechanism by which diet regulates the acetate-to-propionate molar ratio (A: P ratio), we compared the effect on rumen fermentation parameters and the microbiome by altering the ratio of dietary concentrates to roughage ratio and calcium pyruvate infusion. The test animals were Laoshan dairy goats, and were fed continuously through an automatic feeder. The test groups were fed a base diet of low concentrates, and intraruminally infused with calcium pyruvate at two concentrations. The infusion concentrations were derived from the difference in the rate of carbohydrate degradation of the high and low concentrate diets, and they were artificially set such that the high concentration infusion group was infused with twice the concentration as the low concentration infusion group. The control groups were fed high concentrate (6:4) and low concentrate (3:7) diets, respectively. The following results were obtained by measuring rumen fermentation parameters and microbial composition: the rumen A: P ratio was significantly lower in the high-concentrate diet group than in the low concentrate diet group (P < 0.05). Infusion of low concentration calcium pyruvate had no significant effect on rumen A: P ratio (P > 0.05), while infusion of high concentration calcium pyruvate significantly increased the rumen A: P ratio (P < 0.05). Relative to goats fed the low concentrate diet, those fed the high concentrate diet had a greater abundance of microbes related to propionate production and a reduced abundance of microbes related to fiber degradation. Infusion of pyruvate had no significant effect on rumen microbial structure. The above results indicate that increasing the concentration of the fermentation substrate without affecting the composition of the microflora does not reduce the A: P ratio. Microbiological results showed that the A: P ratio was more closely related to the rumen microflora structure. Therefore, it is believed that rumen microflora structure is the main mechanism regulating A: P ratio in rumen fermentation.

Bones and Crohn’s:No benefit of adding sodium fluoride or ibandronate to calcium and vitamin D

AIM: To compare the effect of calcium and cholecalciferol alone and along with additional sodium fluoride or ibandronate on bone mineral density (BMD) and fractures in patients with Crohn's disease (CD). METHODS: Patients (n =148) with reduced BMD (T-score < -1) were randomized to receive cholecalciferol (1000 IU) and calcium citrate (800 mg) daily alone(group A, n = 32) or along with additional sodium fluoride (25 mg bid) (group B, n = 62) or additional ibandronate (1 mg iv/3-monthly) (group C, n = 54). Dual energy X-ray absorptiometry of the lumbar spine (L1-L4) and proximal right femur and X-rays of the spine were performed at baseline and after 1.0, 2.25 and 3.5 years. Fracture-assessment included visual reading of X-rays and quantitative morphometry of vertebral bodies (T4-L4).RESULTS: One hundred and twenty three (83.1%) patients completed the first year for intention-to-treat (ITT) analysis. Ninety two (62.2%) patients completed the second year and 71 (47.8%) the third year available for per-protocol (PP) analysis. With a significant increase in T-score of the lumbar spine by +0.28 ± 0.35 [95% conf idence interval (CI): 0.162-0.460, P < 0.01], +0.33 ± 0.49 (95% CI: 0.109-0.558, P < 0.01), +0.43 ± 0.47 (95% CI: 0.147-0.708, P < 0.01) in group A, +0.22 ± 0.33 (95% CI: 0.125-0.321, P < 0.01); +0.47 ± 0.60 (95% CI: 0.262-0.676, P < 0.01), +0.51 ± 0.44 (95% CI: 0.338-0.682, P < 0.01) in group B and +0.22 ± 0.38 (95% CI: 0.111-0.329, P < 0.01), +0.36 ± 0.53 (95% CI: 0.147-0.578, P < 0.01), +0.41 ± 0.48 (95% CI: 0.238-0.576, P < 0.01) in group C, respectively, during the 1.0, 2.25 and 3.5 year periods (PP analysis), no treatment regimen was superior in any in- or between-group analyses. In the ITT analysis, similar results in all in- and between-group analyses with a significant in-group but non-significant between-group increase in T-score of the lumbar spine by 0.38 ± 0.46 (group A, P < 0.01), 0.37 ± 0.50 (group B, P < 0.01) and 0.35 ± 0.49 (group C, P < 0.01) was observed. Follow-up in ITT analysis was still 2.65 years. One vertebral fracture in the sodium fluoride group was detected. Study medication was safe and well tolerated. CONCLUSION: Additional sodium fluoride or ibandronate had no benefit over calcium and cholecalciferol alone in managing reduced BMD in CD.

Microanalyses of the hydroxyl-poly-calcium sodium phosphate coatings produced by ion beam assisted deposition

Thin calcium phosphate catings on titanium alloy substrates were prepared by Ar^+ ion beam assisted deposition(IBAD) from hydroxyl-poly-calcium sodium phosphate(HPPA) target.The coatings were analyzed by XRD,FTIR,XPS,These analyses revealed that the as-deposited films were amorphous or no apparent crystallinity.No distinct absorption band of the hydroxyl group was observed in FTIR spectra of the coatings but new absorption bands were presented for CO3^-2,The calcium to phosphorous ratio of these catings in different IBAD conditions varied from 0.46 to 3.36.

不同施氮水平下硅肥对谷子抗倒伏能力、产量和品质的影响

[目的]倒伏严重影响谷子产量和品质。探究不同施氮水平下硅肥提高谷子茎秆强度、产量及品质的作用,为谷子高产高效施肥提供技术方案。[方法]以晋谷21和张杂13为供试谷子品种,在山西太谷进行大田试验。在常规施氮量N_(1)(180 kg/hm^(2))和高施氮量N_(2)(450 kg/hm^(2))下,分别设置不施硅、施用硅酸钠(Si_(1),SiO_(2) 68.85 kg/hm^(2))和硅钙肥(Si_(2),SiO_(2) 67.2 kg/hm^(2)),共6个处理。在谷子成熟期测量其株高、抗倒伏能力相关指标、光合特性、产量和品质相关指标,并观察茎秆横切面显微结构。[结果]N_(1)水平下,施用硅肥降低了谷子基节长度,增加了茎粗、茎秆抗折力和穿刺力,晋谷21和张杂13两品种前五基节的节间长度分别降低了4.1%~30.1%和9.5%~11.5%,茎粗分别增加5.3%~19.4%和13.0%~34.1%;晋谷21抗倒性在N_(1)-Si_(1)处理较强,第一、第二基节抗倒伏指数较N_(1)-Si_0处理分别增加37.4%和35.8%,张杂13在N_(1)-Si_(2)处理时较强,第一、第二基节抗倒伏指数较N_(1)-Si_0处理分别增加136.0%和94.7%。N_(2)水平下,施用硅肥后晋谷21和张杂13前五基节的节间长度分别降低了9.6%~30.3%和10.6%~14.9%,茎粗分别增加了9.56%~23.9%和16.2%~31.0%,茎秆扁平度降低。硅钙肥对谷子茎秆强度影响大于硅酸钠,N_(2)-Si_(2)处理晋谷21的第二基节抗折力、穿刺力和抗倒伏指数比N_(2)-Si_0分别增加97.9%、77.6%和83.3%,张杂13的第一基节抗折力、穿刺力和抗倒伏指数比N_(2)-Si_0分别增加74.0%、66.8%和128%。施硅后谷子茎秆中机械组织增厚,维管束数量增多且排列均匀,向茎秆中心延伸,且在N_(2)水平下,硅钙肥作用效果优于硅酸钠。硅可促进谷子穗码发育,增加穗粗、穗粒数和千粒重,在高氮水平下硅钙肥处理使晋谷21和张杂13的产量分别增加23.8%和24.0%。施用硅肥能够提高谷子脂肪、蛋白质和氨基酸含量,在高氮水平下可以降低谷子直链淀粉/支链淀粉值。[结论]在高氮条件下,施用硅钙肥使谷子前五基节长度降低,茎粗增加,机械强度增加,进而提高抗倒伏能力;施用硅肥还可增加光合速率和蒸腾速率,促进物质积累和运输,增加产量,改善品质。

Dry Mix Slag—High-Calcium Fly Ash Binder. Part One: Hydration and Mechanical Properties

High-calcium fly ash (HCFA)—a residue of high-temperature coal combustion at thermal power plants, in combination with sodium carbonate presents an effective hardening activator of ground granulated blast-furnace slag (GGBFS). Substitution of 10% - 30% of GGBFS by HCFA and premixing of 1% - 3% Na2CO3 to this dry binary binder was discovered to give mortar compression strength of 10 - 30 to 30 - 45 MPa at 7 and 28 days when moist cured at ambient temperature. High-calcium fly ash produced from low-temperature combustion of fuel, like in circulating fluidized bed technology, reacts with water readily and is itself a good hardening activator for GGBFS, so introduction of Na2CO3 into such mix has no noticeable effect on the mortar strength. However, low-temperature HCFA has higher water demand, and the strength of mortar is compromised by this factor. As of today, our research is still ongoing, and we expect to publish more data on different aspects of durability of proposed GGBFS-HCFA binder later.

小剂量肝素钠与低分子肝素钙对脓毒症治疗作用的对比研究

目的:对比小剂量肝素钠与低分子肝素钙治疗脓毒症的效果。方法:选取2021年10月—2022年10月脓毒症患者100例,随机分为观察组和对照组,每组50例。对比两组患者的治疗效果。结果:对照组弥散性血管内凝血8例(16.0%),观察组弥散性血管内凝血1例(2.0%),观察组临床疗效高于对照组(P<0.05)。随访1个月,观察组病死率低于对照组(P<0.05)。观察组各项凝血指标显著优于对照组(P<0.05)。观察组各项炎性因子水平低于对照组(P<0.05)。两组治疗后急性生理与健康评分(APACHEⅡ)优于治疗前,且观察组优于对照组,差异有统计学意义(P<0.05)。结论:低分子肝素钙相比小剂量肝素钠治疗脓毒症更加可行,可降低并发症发生率,改善短期预后。

那曲肝素钙和达肝素钠在预防髋膝关节置换术后下肢深静脉血栓形成的临床比较

目的比较那曲肝素钙和达肝素钠在预防髋膝关节置换术后下肢深静脉血栓形成的效果。方法选取2020年3月—2022年3月在本院进行髋膝关节置换术的患者60例为研究对象,按纳入标准和排除标准,将30例使用那屈肝素钙预防下肢深静脉血栓的患者录入为对照组;将30例使用达肝素钠预防下肢深静脉血栓的患者录入为研究组;评定两组术后深静脉血栓形成概率和术后各项指标结果。结果对照组下肢深静脉血栓发生率高于研究组,组间对比差异有统计学意义(P<0.05);两组术中失血量和引流量降低情况比较,组间对比差异无统计学意义(P>0.05),研究组血红蛋白降低程度更明显,组间差异有统计学意义(P<0.05)。术前、术后两组PT以及APTT水平分析,组间对比差异无统计学意义(P>0.05)。结论临床应用达肝素钠和那屈肝素钙,均可有效控制下肢深静脉血栓的发生,但达肝素钠更有利于降低下肢深静脉血栓形成。

利用聚乙烯醇-海藻酸钙固定化Propionibacterium freudenreichii NX-4制备丙酸

以Propionibacterium freudenreichii NX-4为研究对象,采用聚乙烯醇(PVA)和海藻酸钠互配作为固定化载体,考察了其制备丙酸的最佳固定化条件:ρ(PVA)为10.7 g/L,ρ(海藻酸钠)为1.4 g/L,包埋量16%(质量分数),ρ(硼酸)为50 g/L,固定化时间18 h.经15批次的发酵验证,产量稳定,丙酸平均产量为19.64 g/L(葡萄糖40 g/L).以80 g/L的葡萄糖为C源固定化制备丙酸192 h,丙酸产量达35.4 g/L.

钙固化碱焙烧−水浸法从二次铝渣中分离氟和铝

设计一种钙固化碱焙烧−水浸出联合工艺处置二次铝渣,研究CaO用量、NaOH用量、焙烧温度和时间对铝溶出和氟固化行为的影响。在最佳实验条件(焙烧温度1000℃、Al与NaOH摩尔比1꞉0.6、F与CaO摩尔比1꞉2.5、焙烧时间2.0 h)下,氟和铝被分离,其中氟固化率为99.98%,铝溶出率为52.97%。水浸液经蒸发结晶,可得到符合中国工业标准的NaAlO_(2)产品;水浸渣可作为速凝水泥原料。总体而言,此研究为处置二次铝渣提供了一个有效、环保的解决方案。