油田生产中硫酸盐还原菌的危害及其防治

归纳了硫酸盐还原菌在油田生产活动中的危害,并通过对硫酸盐还原菌代谢机制的研究,深入了解其代谢特点和金属腐蚀机制。在此基础上,全面总结了硫酸盐还原菌的防治方法,包括物理方法、化学方法和生物方法,并提出了硫酸盐还原菌的防治策略和未来发展方向。     

Quantitative Standards of 4-O-Acetyl- and 9-O-Acetyl-N-Acetylneuraminic Acid for the Analysis of Plasma and Serum

N-Acetylneuraminic acid (sialic acid, Neu5Ac) is one of a large, diverse family of nine-carbon monosaccharides that play roles in many biological functions such as immune response. Neu5Ac has previously been identified as a potential biomarker for the presence and pathogenesis of cardiovascular disease (CVD), diabetes and cancer. More recent research has highlighted acetylated sialic acid derivatives, specifically Neu5,9Ac₂, as biomarkers for oral and breast cancers, but advances in analysis have been hampered due to a lack of commercially available quantitative standards. We report here the synthesis of 9-O- and 4-O-acetylated sialic acids (Neu5,9Ac₂ and Neu4,5Ac₂) with optimisation of previously reported synthetic routes. Neu5,9Ac₂ was synthesised in 1 step in 68 % yield. Neu4,5Ac₂ was synthesised in 4 steps in 39 % overall yield. Synthesis was followed by analysis of these standards via quantitative NMR (qNMR) spectroscopy. Their utilisation for the identification and quantification of specific acetylated sialic acid derivatives in biological samples is also demonstrated.     

MIF1 and MIF2 Myostatin Peptide Inhibitors as Potent Muscle Mass Regulators

The use of peptides as drugs has progressed over time and continues to evolve as treatment paradigms change and new drugs are developed. Myostatin (MSTN) inhibition therapy has shown great promise for the treatment of muscle wasting diseases. Here, we report the MSTN-derived novel peptides MIF1 (10-mer) and MIF2 (10-mer) not only enhance myogenesis by inhibiting MSTN and inducing myogenic-related markers but also reduce adipogenic proliferation and differentiation by suppressing the expression of adipogenic markers. MIF1 and MIF2 were designed based on in silico interaction studies between MSTN and its receptor, activin type IIB receptor (ACVRIIB), and fibromodulin (FMOD). Of the different modifications of MIF1 and MIF2 examined, _Ac-MIF1 and _Ac-MIF2-_NH2 significantly enhanced cell proliferation and differentiation as compared with non-modified peptides. Mice pretreated with _Ac-MIF1 or _Ac-MIF2-_NH2 prior to cardiotoxin-induced muscle injury showed more muscle regeneration than non-pretreated controls, which was attributed to the induction of myogenic genes and reduced MSTN expression. These findings imply that _Ac-MIF1 and _Ac-MIF2-_NH2 might be valuable therapeutic agents for the treatment of muscle-related diseases.     

Extracellular Matrix Deposition and Remodeling after Corneal Alkali Burn in Mice

Corneal transparency relies on the precise arrangement and orientation of collagen fibrils, made of mostly Type I and V collagen fibrils and proteoglycans (PGs). PGs are essential for correct collagen fibrillogenesis and maintaining corneal homeostasis. We investigated the spatial and temporal distribution of glycosaminoglycans (GAGs) and PGs after a chemical injury. The chemical composition of chondroitin sulfate (CS)/dermatan sulfate (DS) and heparan sulfate (HS) were characterized in mouse corneas 5 and 14 days after alkali burn (AB), and compared to uninjured corneas. The expression profile and corneal distribution of CS/DSPGs and keratan sulfate (KS) PGs were also analyzed. We found a significant overall increase in CS after AB, with an increase in sulfated forms of CS and a decrease in lesser sulfated forms of CS. Expression of the CSPGs biglycan and versican was increased after AB, while decorin expression was decreased. We also found an increase in KS expression 14 days after AB, with an increase in lumican and mimecan expression, and a decrease in keratocan expression. No significant changes in HS composition were noted after AB. Taken together, our study reveals significant changes in the composition of the extracellular matrix following a corneal chemical injury.     

我国硫酸钾工程建设进展

介绍了我国近年来硫酸钾的供需状况。在简述曼海姆法、缔置法、芒硝法、其他复分解法和制盐苦卤法的特点基础上,着重介绍了我国当前采用这几种工艺的硫酸钾厂的生产和建设情况。指出在我国发展硫酸钾工业是大有可为的。     

硫酸镁、硫酸钾镁农业应用现状与前景展望

硫酸镁是世界镁肥生产中产量最高、品种最多的镁肥,围绕硫酸镁、硫酸钾镁在农业中的应用,针对我国海水制盐副产大量的苦卤,介绍了它们的物性参数、化学组成、研发和农业应用情况,认为这两个品种在我国的生产和应用将进一步得到提升。     

Extraction of Mn(II) Ions from Sulphate Solution by 1-Phenyl- 3-Methyl-4-Butyryl-Pyrazolone-5: Influence of pH,Sulphate Concentration,and Additional Complexing Agents

The effect of sulphate ions in a buffered medium on the extraction of manganese(II) (Mn(II)) into 1-phenyl-3-methyl-4-butyryl-pyrazolone-5 (HBuP) in chloroform and benzene solutions has been studied. It showed that extraction at lower pH values is more favorable with solvents that have lower dielectric constants. It is also shown that an increase in sulphate ion concentration in the buffered medium leads to a decrease in Mn(II) extraction and a shift of the extraction process to higher pH values. Slight synergism occurred in the distribution of the metal ion into the benzene-butanol phase and data showed that pH_½ was further shifted to lower values on the addition of butanol into either of the organic phases studied. The slope analysis indicated that Mn(BuP)₂ species were extracted during all the extraction processes. The extraction patterns from solutions of mineral acids, salting out, and auxiliary complexing agents were reported. The pH_½, log K_D, and log K_ex of all the extraction systems were determined and used for explaining the various extraction processes observed.     

Recruiting the Host's Immune System to Target Helicobacter pylori's Surface Glycans

Due to the increased prevalence of bacterial strains that are resistant to existing antibiotics, there is an urgent need for new antibacterial strategies. Bacterial glycans are an attractive target for new treatments, as they are frequently linked to pathogenesis and contain distinctive structures that are absent in humans. We set out to develop a novel targeting strategy based on surface glycans present on the gastric pathogen Helicobacter pylori (Hp). In this study, metabolic labeling of bacterial glycans with an azide‐containing sugar allowed selective delivery of immune stimulants to azide‐covered Hp. We established that Hp's surface glycans are labeled by treatment with the metabolic substrate peracetylated N‐azidoacetylglucosamine (Ac₄GlcNAz). By contrast, mammalian cells treated with Ac₄GlcNAz exhibited no incorporation of the chemical label within extracellular glycans. We further demonstrated that the Staudinger ligation between azides and phosphines proceeds under acidic conditions with only a small loss of efficiency. We then targeted azide‐covered Hp with phosphines conjugated to the immune stimulant 2,4‐dinitrophenyl (DNP), a compound capable of directing a host immune response against these cells. Finally, we report that immune effector cells catalyze selective damage in vitro to DNP‐covered Hp in the presence of anti‐DNP antibodies. The technology reported herein represents a novel strategy to target Hp based on its glycans.     

Metabolic Glycoengineering in hMSC-TERT as a Model for Skeletal Precursors by Using Modified Azide/Alkyne Monosaccharides

Metabolic glycoengineering enables a directed modification of cell surfaces by introducing target molecules to surface proteins displaying new features. Biochemical pathways involving glycans differ in dependence on the cell type; therefore, this technique should be tailored for the best results. We characterized metabolic glycoengineering in telomerase-immortalized human mesenchymal stromal cells (hMSC-TERT) as a model for primary hMSC, to investigate its applicability in TERT-modified cell lines. The metabolic incorporation of N-azidoacetylmannosamine (Ac₄ManNAz) and N-alkyneacetylmannosamine (Ac₄ManNAl) into the glycocalyx as a first step in the glycoengineering process revealed no adverse effects on cell viability or gene expression, and the in vitro multipotency (osteogenic and adipogenic differentiation potential) was maintained under these adapted culture conditions. In the second step, glycoengineered cells were modified with fluorescent dyes using Cu-mediated click chemistry. In these analyses, the two mannose derivatives showed superior incorporation efficiencies compared to glucose and galactose isomers. In time-dependent experiments, the incorporation of Ac₄ManNAz was detectable for up to six days while Ac₄ManNAl-derived metabolites were absent after two days. Taken together, these findings demonstrate the successful metabolic glycoengineering of immortalized hMSC resulting in transient cell surface modifications, and thus present a useful model to address different scientific questions regarding glycosylation processes in skeletal precursors.     

硫酸钾生产工艺与我国硫酸钾工业展望

叙述了硫酸钾生产的四种方法（曼海姆炉法、复分解法、缔置法和钾矿综合利用）,介绍了我国硫酸钾工业现状,指出了我国硫酸钾工业的发展方向。     

Preparation and characterization of ferrous oxalate cement—A novel acid-base cement

Ferrous oxalate cement (FOC), a new type of acid-base cement, is prepared at room temperature through reactions between iron-rich copper slag (CS) and oxalic acid (OA). In this work, the influences of precursor proportions, including the copper slag-to-oxalic acid mass ratio (CS/OA), borax-to-cement mass ratio (B/C), and water-to-cement mass ratio (W/C), on the setting behavior and compressive strength of FOC paste are investigated. Furthermore, the evolutions of pH and ions concentrations are traced to understand the reaction mechanism of FOC. The results show that the compressive strength decreases with an increase in W/C; when W/C is fixed, with an increase in CS/OA, the compressive strength first increases and then decreases, giving an optimal value. The compressive strengths of specimens at 3, 7, and 28 days can reach 33, 41, and 55 MPa, respectively, under the optimal conditions (CS/OA = 3.6, B/C = 0.03, and W/C = 0.18). The setting time is also a function of W/C and CS/OA, and can be extended by adding borax. Iron oxalate hydrate (FeC₂O₄·2H₂O) has been identified as the exclusive hydration product of FOC due to the chemical reaction between Fe₂SiO₄ or Fe₃O₄ contained in CS and OA solution. At the initial stage of reaction, OA is dissolved to release protons, HC₂O₄⁻ and C₂O₄²⁻, which facilitate the dissolution of Fe₂SiO₄ and Fe₃O₄ and the release of Fe²⁺ in the aqueous phase. Then the Fe²⁺ ions combine with HC₂O₄⁻ and C₂O₄²⁻ to precipitate FeC₂O₄·2H₂O, acting as the cementitious phase to bond the unreacted CS particles.     

沿海地区硫酸钾国产化发展趋势

本文为解决我国硫酸钾长期短缺、大量进口而推出的新工艺、新技术。沿海产盐区用兑卤法生产氯化钾消耗高、严重亏损，作者以发展的相平衡理论为基础，在常温下晒制钾肥或用“氨化法制取硫酸钾”形成溴、镁、钠、钾综合利用网络。该工艺制取钾盐转化率高、成本低，将海盐苦卤转废为宝、净化海域，能提高沿海地区卤水化工和环境保护的整体经济效益，使硫酸钾肥国产化，可节约大量外汇，值得在沿海地区因地制宜地推广应用。     

Presence of Potential G-Quadruplex RNA-Forming Motifs at the 5′-UTR of PP2Acα mRNA Repress Translation

RNA G-quadruplex (G4)-forming motifs present at the 5′-UTR of the protein phosphatase (PP2Ac) gene are the regulatory targets of the fragile X mental retardation protein (FMRP), which is weakly expressed in Fragile X patients. Herein, we report that the existence of such G4-forming sequence represses the translation of the PP2Acα gene. This study opens therapeutic avenues to design small molecule ligands that mimic the function of the FMRP.     

聚硅硫酸铝处理黄浦江原水中试研究

用聚硅硫酸铝处理黄浦江原水进行中试研究,以解决冬季低温时硫酸铝混凝效果不佳的问题,结果表明:与硫酸铝相比,在相同投加量情况下,聚硅硫酸铝沉淀池出水浊度可降低50%;在投加量为硫酸铝1/2情况下,聚硅硫酸铝沉淀池出水的浊度仍低于硫酸铝沉淀池出水;残留的铝含量降低,而残留硅的含量没有增加,但投加聚硅硫酸铝会导致滤池水头损失增加。     

An Injectable Enzymatically Crosslinked and Mechanically Tunable Silk Fibroin/Chondroitin Sulfate Chondro-Inductive Hydrogel

An injectable hybrid hydrogel is synthesized, comprising silk fibroin (SF) and chondroitin sulfate (CS) through di-tyrosine formation bond of SF chains. CS and SF are reported with excellent biocompatibility as tissue engineering scaffolds. Nonetheless, the rapid degradation rate of pure CS scaffolds presents a challenge to effectively recreate articular cartilage. As CS is one of the cartilage extracellular matrix (ECM) components, it has the potential to enhance the biological activity of SF-based hydrogel in terms of cartilage repair. Therefore, altering the CS concentrations (i.e., 0 wt%, 0.25 wt%, 0.5 wt%, 1 wt%, and 2 wt%), which are interpenetrated between SF β-sheets and chains, can potentially adjust the physical, chemical, and mechanical features of these hybrid hydrogels. The formation of β-sheets by 30 days of immersion in de-ionized (DI) water can improve the compression strength of the SF/CS hybrid hydrogels in comparison with the same SF/CS hybrid hydrogels in the dried state. Biological investigation and observation depicts proper cell attachment, proliferation and cell viability for C28/I2 cells. Gene expression of sex-determining region YBox 9 (SOX9), Collagen II α1, and Aggrecan (AGG) exhibits positive C3H10T1/2 growth and expression of cartilage-specific genes in the 0.25 wt% and 0.5 wt% SF/CS hydrogels.     

Functionalised supports with sugar dendritic ligand

Functionalised supports with sugar dendritic ligand were obtained from chemical modification on poly(hydroxylated polybutadienic-hydroxyethyl methacrylate) [poly(PB-HEMA)] matrix. The matrix was activated with 1,4 butanediol diglycidyl ether (BDGE) or epichlorohydrin (ECH). Later, a dendritic molecule was immobilised and submitted to react with glucose (GLU) using a carbodiimide reagent. Then, glucose-containing supports were used as sorbents to retain Concanavalin A (Con A).Properties such as equilibrium volume swelling ratios (q_v), extent of conversion of functional groups, amount of bound dendritic molecule and amount of coupled glucose were analysed.     

Adsorption and Quantum Chemical Studies on the Inhibition Potentials of Some Thiosemicarbazides for the Corrosion of Mild Steel in Acidic Medium

Three thiosemicarbazides, namely 2-(2-aminophenyl)-N phenylhydrazinecarbothioamide (AP4PT), N,2-diphenylhydrazinecarbothioamide (D4PT) and 2-(2-hydroxyphenyl)-N-phenyl hydrazinecarbothioamide (HP4PT), were investigated as corrosion inhibitors for mild steel in H₂SO₄ solution using gravimetric and gasometric methods. The results revealed that they all inhibit corrosion and their % inhibition efficiencies (%IE) follow the order: AP4PT > HP4PT > D4PT. The %IE obtained from the gravimetric and gasometric experiments were in good agreement. The thermodynamic parameters obtained support a physical adsorption mechanism and the adsorption followed the Langmuir adsorption isotherm. Some quantum chemical parameters were calculated using different methods and correlated with the experimental %IE. Quantitative structure activity relationship (QSAR) approach was used on a composite index of some quantum chemical parameters to characterize the inhibition performance of the studied molecules. The results showed that the %IE were closely related to some of the quantum chemical parameters, but with varying degrees. The calculated/theoretical %IE of the molecules were found to be close to their experimental %IE. The local reactivity has been studied through the Fukui and condensed softness indices in order to predict both the reactive centers and to know the possible sites of nucleophilic and electrophilic attacks.     

Biological Treatment of Saline Wastewater by Fed-Batch Operation

The adverse effects of salt on biological treatment of saline wastewater inoculated by activated sludge culture were investigated. A synthetic wastewater composed of diluted molasses, urea, KH₂PO₄ and various concentrations of salt (1–5% w/v NaCl) was treated in an aerobic-biological reactor operating in fed-batch mode. An activated sludge culture obtained from a wastewater treatment plant was used as the seed. Variations of chemical oxygen demand (COD) removal rate and efficiency with salt concentration were determined. A rate expression including salt inhibition effect was proposed and kinetic constants were determined by using the experimental data. © 1997 SCI.     

废电解液净化除杂制取硫酸铜研究

介绍了废电解液净化除杂制取硫酸铜的新工艺。在废电解液中加入CH80和CH6 4试剂进行净化除杂 ,净化液进行化学浓缩、结晶 ,便可得到CuSO4 ·5H2 O产品 ,铜的回收率大于 94 %,硫酸铜含量 96 %以上 ,达到GB4 37— 80一级标准