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Octane compositions in sulfuric acid catalyzed isobutane/butene alkylation products: experimental and

Lina Liang, Youzhi Liu, Weizhou Jiao, Qiaoling Zhang, Chao Zhang

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1229-1242 doi: 10.1007/s11705-020-2030-x

摘要： Octanes in alkylation products obtained from industrial alkylation were studied by batch experiments. More than eight octane isomers were identified and quantified by gas chromatography-mass spectrometry. Based on a classic carbenium ion mechanism, the carbocation transition states in concentrated sulfuric acid catalyzed alkylation were investigated using quantum-chemical simulations and predicted the concentration and octane isomerization products including trimethylpentane and dimethylhexane as well as the formation of heavier compounds that resulted from the oligomerization of octane and butene. The agreement between model calculations and experimental data was quite satisfactory. Calculation results indicated that composition and content of trimethylpentanes in the alkylation products were 2,2,4-trimethylpentane>2,3,3-trimethylpentane>2,3,4-trimethylpentane>2,2,3-trimethylpentane whether the 2-butene or -butene acts as olefin. Heavier compounds in the alkylate were primarily formed by the oligomerization of dimethylhexane with 1-butene. Hopefully, the carbocation transition state models developed in this work will be useful for understanding the product distributions of octane in alkylation products.

关键词： sulfuric acid catalyzed alkylation     carbocation reaction     transition state     octane compositions    

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Comparison of prechilling stratification and sulfuric acid scarification on seed germination of

Nan WANG, Jing GAO, Suiqi ZHANG, Feng YAN

《农业科学与工程前沿（英文）》 2017年 第4卷 第2期   页码 220-227 doi: 10.15302/J-FASE-2017146

摘要： In semi-arid regions of the Loess Plateau, water deficiency restricts plant performance. (switchgrass), which is a highly versatile grass, had been introduced to the Plateau as a restoration species. To determine if prechilling stratification (PCS) and sulfuric acid scarification (SAS) can optimize establishment, cvs Pathfinder, Trailblazer and Alamo were tested under different ambient water potentials by measuring germination and root and shoot growth along water potential gradients under laboratory conditions. Both PCS and SAS improved total germination percentage (TGP), with PCS being more beneficial. The effect of PCS and SAS on mean germination time (MGT) weakened gradually with increasing drought stress. Both PCS and SAS showed no obvious effect on promoting root and shoot growth. Both PCS and SAS reduced base water potential requirement for reaching 50% germination of Pathfinder and Trailblazer, with this effect greater for PCS. These results indicate that embryo dormancy may be a major factor limiting germination of under drought conditions. Pathfinder appears to be more suitable for a semi-arid environment, whereas Alamo appears to be unsuitable for drought conditions. Given the large difference between predicted value and measured value, the reliability and applicable scope of linear regression estimated Y needs further investigation, specification and optimization.

关键词： base water potential     data analysis method     embryo growth     germination    

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Resistance to acid degradation, sorptivity, and setting time of geopolymer mortars

Osama A MOHAMED; Rania AL-KHATTAB; Waddah AL-HAWAT

《结构与土木工程前沿（英文）》 2022年 第16卷 第6期   页码 781-791 doi: 10.1007/s11709-022-0862-9

摘要： Experimental evaluations were conducted to determine the water sorptivity, setting time, and resistance to a highly acidic environment, of mortar with alkali-activated ground granulated blast furnace slag (GBS) binder and also of combinations of fly ash and GBS binders. Binders were activated using mixtures of NaOH and Na2SiO3 solutions. The molarity of NaOH in the mixtures ranged from 10 mol·L−1 to 16 mol·L−1, and the Na2SiO3/NaOH ratio was varied from 1.5 to 2.5. Mortar samples were produced using three binder combinations: 1) GBS as the only binder; 2) blended binder with a slag-to-fly ash ratio of 3:1; and 3) mixed binder with 1:1 ratio of slag to fly ash. Mortar samples were mixed and cured at (22 ± 2) °C till the day of the test. The impact of activator solution alkalinity, activator ratio Na2SiO3/NaOH, GBS content on the rate of water absorption were evaluated. After 7, 28, and 90 d of immersion in a 10% sulfuric acid solution, the resistance of a geopolymer matrix to degradation was assessed by measuring the change in sample weight. The influence of solution alkalinity and relative fly ash content on setting times was investigated. Alkali-activated mortar with a slag-to-fly ash ratio of 3:1 had the least sorptivity compared to the two other binder combinations, at each curing age, and for mortars made with each of the NaOH alkaline activator concentrations. Mortar sorptivity decreased with age and sodium hydroxide concentrations, suggesting the production of geopolymerization products. No reduction in weight of sample occurred after immersion in the strong acid H2SO4 solution for three months, regardless of binder combination. This was due to the synthesis of hydration and geopolymerization products in the presence of curing water, which outweighed the degradation of the geopolymer matrix caused by sulfuric acid.

关键词： alkali-activated materials     fly ash     sorptivity     durability of concrete     sodium hydroxide     sodium silicates     reduction in CO2 emissions     sulfuric acid    

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绿色化的磷复肥生产集成工艺

冯怡生

《中国工程科学》 1999年 第1卷 第1期   页码 58-62

摘要：

磷复肥生产排放的磷石膏废渣堆存占地，污染环境，已成为亟待解决的难题。利用磷石膏制硫酸与水泥，可消除污染，实现硫资源的良性循环，使经济效益、社会效益和环境效益有机统一，促进了磷复肥工业的可持续发展。

关键词： 磷复肥     磷石膏     硫酸     水泥    

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One-step synthesis of

Kuiyi YOU, Fangfang ZHAO, Xueyan LONG, Pingle LIU, Qiuhong AI, Hean LUO

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 389-394 doi: 10.1007/s11705-012-1218-0

摘要： A simple and efficient approach for the synthesis of -caprolactam via the liquid phase nitrosation of cyclohexane and nitrosyl sulfuric acid in the presence of concentrated sulfuric acid has been developed. A series of novel AlVPO composites were prepared by an impregnation method and the composites were then employed to catalyze the nitrosation reaction of cyclohexane and nitrosyl sulfuric acid. Compared to the reaction using fuming sulfuric acid, the selectivity for the desired product was significantly improved using this one-step catalytic process. This method affords a shortcut to prepare -caprolactam and its analogs from cyclohexane.

关键词： cyclohexane     ?-caprolactam     AlVPO composite catalysts     one-step synthesis     concentrated sulfuric acid    

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Sulfonic acid-functionalized mesoporous silica catalyst with different morphology for biodiesel production

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1198-1210 doi: 10.1007/s11705-021-2133-z

摘要： Sulfonic acid functionalized mesoporous silica based solid acid catalysts with different morphology were designed and fabricated. The synthesized materials were characterized by various physicochemical and spectroscopic techniques like scanning electron microscope-energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller surface area, thermogravimetric analysis and n-butylamine acidity. The shape of catalysts particles plays an important role in its activity. The sulfonic acid functionalized mesoporous silica catalysts of spherical shape and the cube shape were assessed for catalytic activity in biodiesel production. The catalytic biodiesel production reaction over the catalysts were studied by esterification of free fatty acid, oleic acid with methanol. The effect of various reaction parameters such as catalyst concentration, acid/alcohol molar ratio, catalyst amount, reaction temperature and reaction time on catalytic activity were investigated to optimize the conditions for maximum conversion. It was sulfonated cubic shape mesoporous silica which exhibited better activity as compared to the spherical shape silica catalysts. Additionally, the catalyst was regenerated and reused up to three cycles without any significant loss in activity. The present catalysts exhibit superior performance in biodiesel production and it can be used for the several biodiesel feedstock’s that are rich in free fatty acids.

关键词： solid acid catalyst     mesoporous silica     sulfonic acid     biodiesel     esterification     oleic acid    

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Amino acid promoted hydrogen battery system using Mn-pincer complex for reversible CO hydrogenation toformic acid

《能源前沿（英文）》 2022年 第16卷 第5期   页码 697-699 doi: 10.1007/s11708-022-0843-7

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Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

《化学科学与工程前沿（英文）》 2023年 第17卷 第6期   页码 784-794 doi: 10.1007/s11705-022-2278-4

摘要： In situ encapsulation is an effective way to synthesize enzyme@metal–organic framework biocatalysts; however, it is limited by the conditions of metal–organic framework synthesis and its acid-base stability. Herein, a biocatalytic platform with improved acid-base stability was constructed via a one-pot method using bismuth-ellagic acid as the carrier. Bismuth-ellagic acid is a green phenol-based metal–organic framework whose organic precursor is extracted from natural plants. After encapsulation, the stability, especially the acid-base stability, of amyloglucosidases@bismuth-ellagic acid was enhanced, which remained stable over a wide pH range (2–12) and achieved multiple recycling. By selecting a suitable buffer, bismuth-ellagic acid can encapsulate different types of enzymes and enable interactions between the encapsulated enzymes and cofactors, as well as between multiple enzymes. The green precursor, simple and convenient preparation process provided a versatile strategy for enzymes encapsulation.

关键词： bismuth-ellagic acid     in situ encapsulation     enzyme@MOF biocomposites    

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Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2101-2113 doi: 10.1007/s11705-023-2361-5

摘要： In response to the reduction of food production and economic losses caused by plant bacterial diseases, it is necessary to develop new, efficient, and green pesticides. Natural products are rich and sustainable source for the development of new pesticides due to their low toxicity, easy degradation, and eco-friendliness. In this study, we prepared three series of ursolic acid derivatives and assessed their antibacterial ability. Most target compounds exhibited outstanding antibacterial activities. Among them, the relative optimal EC50 values of Xanthomonas oryzae pv. oryzae and Xanthomonas axonopodis pv. citri were 2.23 (A17) and 1.39 (A16) μg·mL–1, respectively. The antimicrobial mechanism showed that compound A17 induced an excessive accumulation and production of reactive oxygen species in bacteria and damaged the cell membrane integrity to kill bacteria. More interestingly, the addition of low concentrations of exogenous hydrogen peroxide enhanced the antibacterial efficacy of compound A17 against Xanthomonas oryzae pv. oryzae. These entertaining results suggested that compound A17 induced an apparent apoptotic behavior in the tested bacteria. Overall, we developed the promising antimicrobial agents that destroyed the redox system of phytopathogenic bacteria, further demonstrating the unprecedented potential of ursolic acid for agricultural applications.

关键词： ursolic acid     antibacterial activities     reactive oxygen species     apoptosis    

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Synergistic scale inhibition of polyaspartic acid composite with magnetic field

LIU Zhenfa, WANG Yanji, GAO Yuhua, ZHANG Lihui

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 261-265 doi: 10.1007/s11705-007-0047-z

摘要： Polyaspartic acid (PASP) composite, a scale inhibitor, was prepared from PASP, itaconic acid–acrylic acid–acrylic ester (IA-AA-AE) terpolymer and 2-phosphonobutane- 1,2,4-tricarboxylic acid (PBTCA). The scale inhibition of PASP composite and the effect of its synergism with a magnetic field on scale inhibition were investigated. Calcium carbonate crystals in scale samples were characterized by means of SEM and XRD. The static and dynamic experiments show that the chelating function of PASP composite for Ca can be enhanced by synergism with a magnetic field. Under Ca 650 mg/L, HCO 1,300 mg/L and PASP composite 4 mg/L, the scale inhibition rate of PASP composite in magnetic water can increase by 10% in static state and by 20% in dynamic experiments. Scanning electron microscope (SEM) and X-ray diffraction (XRD) results show that calcite and aragonite can be completely transformed into vaterite by using PASP composite.

关键词： synergism     magnetic     PBTCA     dynamic     acid–acrylic acid–acrylic    

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Abiotic association of phthalic acid esters with humic acid of a sludge landfill

Xiaoli CHAI, Yongxia HAO, Xin ZHAO, Guixiang LIU, Ying ZHU, Rong JI, Jun WU, Huanhuan TONG, Youcai ZHAO

《环境科学与工程前沿（英文）》 2012年 第6卷 第6期   页码 778-783 doi: 10.1007/s11783-012-0434-7

摘要： The abiotic association between phthalic acid esters (PAEs) and humic substances (HS) in sludge landfill plays an important role in the fate and stability of PAEs. An equilibrium dialysis combined with C-labeling was used to study the abiotic association of two abundant PAEs (diethyl phthalate and di- -butyl phthalate) with humic acid (HA) isolated from a sludge landfill with different stabilization times and different molecular weights. Elemental analysis and Fourier Transform Infrared Spectrophotometer (FTIR) suggested that high value of HA was related to the high aromatic content and large molecular weight of HA. The results indicated that the association strength of PAEs with HA depended on both the properties of the PAEs and the characteristics of HA. The values of the association were strongly dependent on solution pH, and decreased dramatically as the pH was increased from 3.0 to 9.0. The results suggested that non-specific hydrophobic interaction between PAEs and HA was the main contributor to the association of the PAEs with HA. The interactive hydrogen-bonds between the HA and the PAEs molecules may also be involved in the association.

关键词： abiotic association     phthalic acid esters (PAEs)     humic acid     sludge     landfill    

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New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

《环境科学与工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11783-024-1786-5

摘要：

● The historical development of free nitrous acid (FNA) technologies is reviewed.

关键词： Free nitrous acid     Acid-tolerant ammonia oxidizer     In situ generation     Wastewater management    

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Genomic and metabolomic analysis of with enhanced poly--glutamic acid production through atmospheric

《化学科学与工程前沿（英文）》 2022年 第16卷 第12期   页码 1751-1760 doi: 10.1007/s11705-022-2211-x

摘要： Poly-γ-glutamic acid is an extracellular polymeric substance with various applications owing to its valuable properties of biodegradability, flocculating activity, water solubility, and nontoxicity. However, the ability of natural strains to produce poly-γ-glutamic acid is low. Atmospheric and room temperature plasma was applied in this study to conduct mutation breeding of Bacillus licheniformis CGMCC 2876, and a mutant strain M32 with an 11% increase in poly-γ-glutamic acid was obtained. Genome resequencing analysis identified 7 nonsynonymous mutations of ppsC encoding lipopeptide synthetase associated with poly-γ-glutamic acid metabolic pathways. From molecular docking, more binding sites and higher binding energy were speculated between the mutated plipastatin synthase subunit C and glutamate, which might contribute to the higher poly-γ-glutamic acid production. Moreover, the metabolic mechanism analysis revealed that the upregulated amino acids of M32 provided substrates for glutamate and promoted the conversion between L- and D-glutamate acids. In addition, the glycolytic pathway is enhanced, leading to a better capacity for using glucose. The maximum poly-γ-glutamic acid yield of 14.08 g·L–1 was finally reached with 30 g·L–1 glutamate.

关键词： ARTP mutagenesis     Bacillus licheniformis     poly-γ-glutamic acid     metabolomics    

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Proline-2′-deoxymugineic acid, a phytosiderophore analog, drives beneficial rhizobacterial community

《农业科学与工程前沿（英文）》 doi: 10.15302/J-FASE-2023531

摘要：

● Proline-2′-deoxymugineic (PDMA) significantly altered the bacterial community in the peanut rhizosphere.

关键词： Beneficial rhizobacteria recruitment     peanut     plant-soil micronutrition enhancement     proline-2′-deoxymugineic acid     stable microbial network    

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Untargeted metabolomic analysis of pregnant women exposure to perfluorooctanoic acid at different degrees

《环境科学与工程前沿（英文）》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1628-x

摘要：

● Metabolome can distinguish pregnant women exposure to PFOA at different degrees.

关键词： Perfluorooctanoic acid     Exposure     Pregnant women     Metabolomic     GSH     Microbiota metabolism    

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标题 作者 时间 类型 操作

Octane compositions in sulfuric acid catalyzed isobutane/butene alkylation products: experimental and

Lina Liang, Youzhi Liu, Weizhou Jiao, Qiaoling Zhang, Chao Zhang

期刊论文

Comparison of prechilling stratification and sulfuric acid scarification on seed germination of

Nan WANG, Jing GAO, Suiqi ZHANG, Feng YAN

期刊论文

Resistance to acid degradation, sorptivity, and setting time of geopolymer mortars

Osama A MOHAMED; Rania AL-KHATTAB; Waddah AL-HAWAT

期刊论文

绿色化的磷复肥生产集成工艺

冯怡生

期刊论文

One-step synthesis of

Kuiyi YOU, Fangfang ZHAO, Xueyan LONG, Pingle LIU, Qiuhong AI, Hean LUO

期刊论文

Sulfonic acid-functionalized mesoporous silica catalyst with different morphology for biodiesel production

期刊论文

Amino acid promoted hydrogen battery system using Mn-pincer complex for reversible CO hydrogenation toformic acid

期刊论文

Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

期刊论文

Discovery of novel ursolic acid derivatives as effective antimicrobial agents through a ROS-mediated

期刊论文

Synergistic scale inhibition of polyaspartic acid composite with magnetic field

LIU Zhenfa, WANG Yanji, GAO Yuhua, ZHANG Lihui

期刊论文

Abiotic association of phthalic acid esters with humic acid of a sludge landfill

Xiaoli CHAI, Yongxia HAO, Xin ZHAO, Guixiang LIU, Ying ZHU, Rong JI, Jun WU, Huanhuan TONG, Youcai ZHAO

期刊论文

New perspectives in free nitrous acid (FNA) uses for sustainable wastewater management

期刊论文

Genomic and metabolomic analysis of with enhanced poly--glutamic acid production through atmospheric

期刊论文

Proline-2′-deoxymugineic acid, a phytosiderophore analog, drives beneficial rhizobacterial community

期刊论文

Untargeted metabolomic analysis of pregnant women exposure to perfluorooctanoic acid at different degrees

期刊论文