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The transformation of PAHs in the sewage sludge incineration treatment

Hui ZHANG,Le XU,Yifei ZHANG,Mengchan JIANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第2期   页码 336-340 doi: 10.1007/s11783-014-0766-6

摘要： The release of pollutants from sewage sludge in the treatment process is a worldwide tricky problem in the field of sludge treatment. In this paper, the release and reaction between monomers of polycyclic aromatic hydrocarbons (PAHs) in the sewage sludge incineration treatment were studied based on simulated experiments. The result indicates that the transformation may occurre between monomers of PAHs during their release in the treatment. Over 90% of total PAHs in sewage sludge are released at the the temperature of 300°C–750°C. The possible transformation of Naphthalene to indeno(1, 2, 3-cd)pyrene was related to the temperature of the treatment system. Here, we showed that the output rate of transformation reactions for indeno(1, 2, 3-cd)pyrene is 94% at 300°C. These findings, by identifying corresponding treatment conditions as well as techniques, can help to understand the reactions and control real outputs of PAHs in the treatment process.

关键词： release of monomers     transformation of monomers     PAHs     sewage sludge     incineration treatment    

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Progress on cleaner production of vinyl chloride monomers over non-mercury catalysts

Jinli ZHANG, Nan LIU, Wei LI, Bin DAI

《化学科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 514-520 doi: 10.1007/s11705-011-1114-z

摘要： Polyvinyl chloride (PVC) has become the third most used plastic after polyethylene and polypropylene and the worldwide demand continues to increase. Polyvinyl chloride is produced by polymerization of the vinyl chloride monomer (VCM), which is manufactured industrially via the dehydrochlorination of dichloroethane or the hydrochlorination of acetylene. Currently PVC production through the acetylene hydrochlorination method accounts for about 70% of the total PVC production capacity in China. However, the industrial production of VCM utilizes a mercuric chloride catalyst to promote the reaction of acetylene and hydrogen chloride. During the hydrochlorination, the highly toxic mercuric chloride tends to sublime, resulting in the deactivation of the catalyst and also in severe environmental pollution problems. Hence, for China, it is necessary to explore environmental friendly non-mercury catalysts for acetylene hydrochlorination as well as high efficiency novel reactors, with the aim of sustainable PVC production via the acetylene-based method. This paper presents a review of non-mercury heterogeneous and homogeneous catalysts as well as reactor designs, and recommends future work for developing cleaner processes to produce VCM over non-mercury catalysts with high activity and long stability.

关键词： polyvinyl chloride     vinyl chloride monomer     acetylene hydrochlorination     non-mercury catalysts     green chemical process    

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Design of nanocarriers for efficient cellular uptake and endosomal release of small molecule and nucleic

Vaibhav Mundra, Ram I. Mahato

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 387-404 doi: 10.1007/s11705-014-1457-3

摘要： There are many challenges in developing efficient and target specific delivery systems of small molecule and nucleic acid drugs. Cell membrane presents one of the major barriers for the penetration of hydrophilic macromolecules across the plasma membrane. Nanocarriers have been designed to enhance their cellular uptake via endocytosis but following their cellular uptake, endosomal escape is the rate limiting step which restricts the value associated with the enhanced uptake by nanocarriers. Viruses are an excellent model for efficient cytosolic delivery by nanocarriers. Viruses exploit intracellular cues to release the genome to cytosol. In this review, we first discuss different endocytic uptake pathways and endosomal escape mechanisms. We then summarize the existing tools for studying the intracellular trafficking of nanocarriers. Finally, we highlight the important design elements of recent virus-based nanocarriers for efficient cellular uptake and endosomal escape.

关键词： nanocarrier     cellular uptake     endosomal release     nucleic acid drug    

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Semi-solid materials for controlled release drug formulation: current status and future prospects

Michelle TRAN,Chun WANG

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 225-232 doi: 10.1007/s11705-014-1429-7

摘要： Semi-solid materials represent an important category of inactive ingredients (excipients) of pharmaceutical products. Here we review several common semi-solid polymers currently used in the controlled release formulations of many drugs. These polymers are selected based on their importance and broad scope of application in FDA-approved drug products and include several polysaccharides (cellulose, starch, chitosan, alginate) and carbomers, a group of mucoadhesive synthetic polymers. Glyceride-based polymers used in self-emulsifying drug delivery systems (SEDDS) will also be discussed for its importance in formulating poorly water-soluble drugs. Unique features and advantages of each type of semi-solid materials are discussed and examples of their use in oral delivery of drugs are provided. Finally, future prospects of developing new and better semi-solid excipients are discussed with the objective of facilitating clinical translation.

关键词： controlled release     drug delivery     semi-solids     polymer     excipient    

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Study on the NOx release rule along the boiler during pulverized coal combustion

JIN Jing, ZHANG Zhongxiao, LI Ruiyang

《能源前沿（英文）》 2007年 第1卷 第1期   页码 91-95 doi: 10.1007/s11708-007-0009-7

摘要： Numerical simulation and experimental study on NO release along the boiler during pulverized coal combustion have been conducted. With the increase of temperature the NO emission increased and the peak value of NO release moved forward. But when the temperature increased to a certain degree, NO emission began to reduce. NO emission increased with the increase of nitrogen content of coal. The peak value of NO release moved backwards with the increase of coal rank. NO emission increased obviously with the increase of stoichiometric ratio. There existed a critical average diameter of the pulverized coal (). If "d, NO emission reduced with the decrease of pulverized coal size. If >, NO emission reduced with the increase of the pulverized coal size. The results showed that the simulation results are in agreement with the experimental results for concentration distribution of NO along the axis of the furnace.
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Capacity estimation and preliminary strategy for reducing the release of dioxins in China

YU Gang, ZHANG Qing, HUANG Jun, CAI Zhenxiao, SUI Qian

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 13-17 doi: 10.1007/s11783-007-0002-8

摘要： As a party of the Stockholm Convention on Persistent Organic Pollutants, China must submit its national implementation plan (NIP) for this convention. The strategy and action plan for reducing the release of dioxins in China are the most important components of the NIP. Three problems are key points for developing such strategy and action plan what are the key sources for applying the best available technology/best environmental practice (BAT/BEP) to reduce the release of dioxins? How about the capacity for reducing the dioxins release from the key sources? Where are the areas of priority for applying BAT/BEP? This paper shows the efforts towards the solution of these problems. The list of key sources covering about half of the total dioxins release was determined considering four criteria. The capacity of key sources were estimated based on the difference between the emission factor corresponding to the actual situation in 2004 and that corresponding to the scenario that all key sources have been applied BAT/BEP to reduce the dioxins release. The priority analysis using the geographical information system (GIS) tool has revealed that eastern provinces should be of high priority in the future reduction activities of dioxins release in China.

关键词： GIS     difference     capacity     scenario     implementation    

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Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 498-510 doi: 10.1007/s11705-014-1451-9

摘要： Design of biocompatible and biodegradable polymer systems for sustained and controlled release of bioactive agents is critical for numerous biomedical applications. Here, we designed, synthesized, and characterized four polyurethane carrier systems for controlled release of model drugs. These polyurethanes are biocompatible and biodegradable because they consist of biocompatible poly(ethylene glycol) or poly(caprolactone diol) as soft segment, linear aliphatic hexamethylene diisocyanate or symmetrical aliphatic cyclic dicyclohexylmethane-4,4′-diisocyanate as hard segment, and biodegradable urethane linkage. They were characterized with Fourier transform infrared spectroscopy, atomic force microscope, and differential scanning calorimetry, whereas their degradation behaviors were investigated in both phosphate buffered saline and enzymatic solutions. By tuning polyurethane segments, different release profiles of hydrophobic and hydrophilic drugs were obtained in the absence and presence of enzymes. Such difference in release profiles was attributed to a complex interplay among structure, hydrophobicity, and degradability of polyurethanes, the size and hydrophobicity of drugs, and drug-polymer interactions. Different drug-polyurethane combinations modulated the distribution and location of the drugs in polymer matrix, thus inducing different drug release mechanisms. Our results highlight an important role of segmental structure of the polyurethane as an engineering tool to control drug release.

关键词： phase structure     degradation     polyurethanes     controlled release     drug delivery    

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Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

Jun-Su Zhou,Long Cheng,Yuan Gao,Zhan-Peng Ge,Bin Zhou,Jing-Ya Li,Jin-Xin Zhao,Jian-Min Yue,

《工程（英文）》 doi: 10.1016/j.eng.2023.09.015

摘要： Four new norditerpenoid heterodimers with different dimerization patterns—namely, trigofragiloids A–C (denoted as compounds 1–3) and (+)- and (−)-trigofragiloid D (compound 4)—and three new phenanthrenone norditerpenoids—namely, trigofragiloids E–G (compounds 5–7)—were isolated from Trigonostemon fragilis. Compounds 1 and 2 feature a novel heterodimeric carbon skeleton formed by the conjugation of a tetra-norditerpenoid and an ennea-norditerpenoid; they have been identified as class 2 atropisomers by means of quantum chemical calculations. Compound 3 is an unprecedented phenylpropanoid-norditerpenoid adduct with a new dimerization pattern. Compounds (+)- and (−)-4 are the first example of S-shaped 1,4-dioxane-fused norditerpenoid dimers. Inspired by the structure elucidation of compound 4, two co-occurring analogues, actephilol A and epiactephilol A, were structurally revised as a pair of geometrical isomers and were identified as two pairs of enantiomers, (+)- and (−)-8 and (+)- and (−)-9, respectively. Their structures were characterized using a combined method. Notably, compound 7 exhibits remarkable adenosine triphosphate-citrate lyase (ACLY) inhibition with a half-maximal inhibition concentration (IC50) value of (0.46 ± 0.11) μmol∙L−1, as active as the positive control BMS-303141, and a molecular docking study offers deep insight into the interaction between compound 7 and ACLY.

关键词： Norditerpenoid heterodimer     Trigonostemon fragilis     Euphorbiaceae     Trigofragiloid     Structural revision     adenosine triphosphate-citrate lyase (ACLY) inhibitory activity    

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functional supramolecular nanoparticles based on pillar[5]arene for controlled generation, storage and release

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 307-313 doi: 10.1007/s11705-022-2216-5

摘要： The storage and controlled release of singlet oxygen (1O2) have attracted increasing attention due to the wide application and microsecond lifetime of 1O2 in water. Herein we provide an integrated nanoplatform consisting of a diphenylanthracene derivative, a water-soluble pillar[5]arene and a photosensitizer tetrakis(4-hydroxyphenyl)porphyrin (TPP), that may provide the controlled generation, storage and release of singlet oxygen. We design a new diphenylanthracene derivative with two trimethylammonium bromide groups on both ends that can be well recognized by the pillar[5]arene. The formed nanocarriers can be used to load TPP through their supramolecular self-assembly. The resulting nanoparticles show good water-solubility and uniform spherical morphology. After laser irradiation (660 nm), the nanoparticles exhibit excellent ability for the generation and storage of 1O2. When the irradiated nanoparticles are heated above 80 °C, 1O2 can be released from the system. Therefore, in this paper we pioneer the use of noncovalent interaction to integrate the diphenylanthracene derivatives and photosensitizers into one functional system, which provides a new strategy for the controlled generation, storage and release of singlet oxygen. We believe this groundbreaking strategy will have a great potential in providing necessary amounts of 1O2 for the photodynamic therapy of tumors in dark.

关键词： storage and controlled release of singlet oxygen     supramolecular nanoparticles     noncovalent interactions     pillararenes     diphenylanthracene     photosensitizers    

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Phosphorus release potential and pollution characteristics of sediment in downstream Nansi Lake, China

Zhijian LI, Qinyan YUE, Baoyu GAO, Yanwen WANG, Qing LIU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 162-170 doi: 10.1007/s11783-011-0313-7

摘要： The research aimed to evaluate present and potential phosphorous pollution due to high sedimentary phosphorus load and release from sediment, when external phosphorus was reduced in downstream Nansi Lake. Pollution load of the sediment and overlying water was investigated. Kinetics and isotherms of adsorption/release of sedimentary phosphorus were studied to determine equilibrium phosphate concentration (EPC ) and release potential. Kinetics of phosphorus adsorption on sediment and release from sediment were well described by both the pseudo-first-order rate equation and the pseudo-second-order rate equation, but more appropriate to the pseudo-second-order rate equation with the adsorption/release capacity more close to the measured values, suggesting that the processes were chemically rate controlled and dependent on adsorption capacity. Soluble reactive phosphorus (SRP) sorption isotherms on sediment were best fitted by the modified Langmuir model indicating a monolayer adsorption. By comparing EPC and SRP of water, the status (adsorption, releasing or in equilibrium) of sediment phosphorus could be determined. The sediments at site S1, S3, S4, S5, and S7 where the EPC s were greater than the SRPs, had a potential to release phosphorus into the water column. However, those sediments at S9, S10, and S12, where the EPC s were approximately equal to the SRPs, were in impermanent equilibrium with overlying water in status of phosphorus, the sediments can be likely to release phosphorus to the water column once the equilibrium was broken. Therefore, sedimentary phosphorus can be a secondary pollution source in downstream Nansi Lake.

关键词： Nansi Lake     sediment     phosphorus     release potential     equilibrium phosphate concentration    

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Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

《化学科学与工程前沿（英文）》 2014年 第8卷 第4期   页码 465-470 doi: 10.1007/s11705-014-1452-8

摘要： The utilization of poly (2-hydroxyethylmethacrylate) grafted agar (Ag-g-P(HEMA)) as a matrix for the controlled release of 5-aminosalicylic acid was investigated. Grafted copolymers of 2-hydroxyethylmethacrylate (HEMA) monomers on agar were synthesized by microwave assisted method. drug release studies were performed at pH values of 2 and 7 in order to investigate the possibility of pH triggered release for colon targeted drug delivery. Further, the percent grafting . (the time taken for release of 50% of the enclosed drug) value was studied and the results indicate that it may be possible to develop a programmable drug release matrix based on grafted polysaccharide. Ag-g-P(HEMA) appears to be a useful matrix for controlled release.

关键词： agar     controlled drug release     5-Amino salicylic acid     poly(2-hydroxyethylmethacrylate) grafted agar    

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Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1463-x

摘要：

• Lanthanum modified bentonite (LMB) can effectively absorb phosphorus (P).

关键词： Sediment     Eutrophication     Thin-layer capping     Phosphorus     Nitrogen     Aluminum-based P-inactivation agent    

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Effect of Fe on NO release during char combustion in air and O

Ying GU, Xiaowei LIU, Bo ZHAO, Minghou XU

《能源前沿（英文）》 2012年 第6卷 第2期   页码 200-206 doi: 10.1007/s11708-012-0181-2

摘要： The chemistry of char was probed by studying nitrogen release under the reactions with air and oxy-fuel combustion. The experiments were conducted in a drop tube furnace and a fixed bed flow reactor. NO was observed during those experiments. The results show that the particle size of char generated at 1073 K in CO is larger than that in N . However, at 1573 K, it is smaller in CO atmosphere due to particle breaking by gasification of char and CO . The Fe addition increases the NO conversion ratio, and the effect of Fe rises steeply with the process going until it becomes stable in the end. The results also indicate that the release of NO increases more significantly with the Fe addition in oxy-fuel environment.

关键词： NO     Fe     char     combustion     CO2    

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Experimental investigations of frost release by hydrophilic surfaces

Zhongliang LIU, Lingyan HUANG, Yujun GOU, Yaomin LIU

《能源前沿（英文）》 2010年 第4卷 第4期   页码 475-487 doi: 10.1007/s11708-010-0114-x

摘要： Frost formation occurs when water vapor in the surrounding air comes into contact with cold surfaces through heat and mass transfer. It is usually an undesirable phenomenon in most refrigeration and cryogenic systems. A few studies have shown that changing the surface energy, such as increasing the surface hydrophilicity or hydrophobicity, has significant effects on frost growth. In this paper, a kind of hydrophilic polymer paint is formulated to counteract frost deposition on cold surfaces. The coated surface can retard frost formation up to three hours under low plate temperatures (-15.3°C) and high air humidity (72%). To test the antifrosting performance of the hydrophilic paint under more practical conditions, it is applied to a fin-and-tube heat exchanger and a domestic refrigerator at a coating thickness of 30 μm. Comparisons of frost deposition, pressure drops, and outlet temperatures are made between uncoated and coated heat exchangers. Under conditions of high air temperature (2.2°C) and relative high air humidity (90%), the paint prolongs the defrosting interval from 80 to 137 min. Experimental observations also show that the coated hydrophilic fins are free of frost deposition during the entire course of the test and that the coating has no significant additional thermal resistance.

关键词： frost formation     hydrophilicity     heat and mass transfer     performance    

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Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

GENG Jinju, WANG Qiang, WANG Xiaorong, NIU Xiaojun

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 120-124 doi: 10.1007/s11783-007-0022-4

摘要： Effects of pH, temperature, and oxygen on the production and release of phosphine in eutrophic lake sediments were investigated under laboratory tests. Results indicated that the elimination of matrix-bound phosphine was accelerated under initial pH 1 or 12. Phosphine levels could reach maximum under initial pH 10. The contents of phosphine increased with the addition of alkali under pH 4 12. The rates of phosphine production and release from lake sediments varied with temperature. 20?C was the most favorable temperature for the production of matrix-bound phosphine. Oxygen showed little effect on matrix-bound phosphine. Matrix-bound phosphine concentrations in lake sediments were concluded to be dependent on a balance of natural generation and depletion processes.
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标题 作者 时间 类型 操作

The transformation of PAHs in the sewage sludge incineration treatment

Hui ZHANG,Le XU,Yifei ZHANG,Mengchan JIANG

期刊论文

Progress on cleaner production of vinyl chloride monomers over non-mercury catalysts

Jinli ZHANG, Nan LIU, Wei LI, Bin DAI

期刊论文

Design of nanocarriers for efficient cellular uptake and endosomal release of small molecule and nucleic

Vaibhav Mundra, Ram I. Mahato

期刊论文

Semi-solid materials for controlled release drug formulation: current status and future prospects

Michelle TRAN,Chun WANG

期刊论文

Study on the NOx release rule along the boiler during pulverized coal combustion

JIN Jing, ZHANG Zhongxiao, LI Ruiyang

期刊论文

Capacity estimation and preliminary strategy for reducing the release of dioxins in China

YU Gang, ZHANG Qing, HUANG Jun, CAI Zhenxiao, SUI Qian

期刊论文

Synthesis and characterization of biocompatible polyurethanes for controlled release of hydrophobic and

Juichen YANG,Hong CHEN,Yuan YUAN,Debanjan SARKAR,Jie ZHENG

期刊论文

Highly Aromatic Norditerpenoid Heterodimers and Monomers from Trigonostemon fragilis

Jun-Su Zhou,Long Cheng,Yuan Gao,Zhan-Peng Ge,Bin Zhou,Jing-Ya Li,Jin-Xin Zhao,Jian-Min Yue,

期刊论文

functional supramolecular nanoparticles based on pillar[5]arene for controlled generation, storage and release

期刊论文

Phosphorus release potential and pollution characteristics of sediment in downstream Nansi Lake, China

Zhijian LI, Qinyan YUE, Baoyu GAO, Yanwen WANG, Qing LIU

期刊论文

Controlled drug release of 5-amino salicylic acid by poly(2-hydroxyethylmethacrylate) grafted agar

G. Usha RANI,Kartick Prasad DEY,Srijita BHARTI,Sumit MISHRA

期刊论文

Four kinds of capping materials for controlling phosphorus and nitrogen release from contaminated sediment

期刊论文

Effect of Fe on NO release during char combustion in air and O

Ying GU, Xiaowei LIU, Bo ZHAO, Minghou XU

期刊论文

Experimental investigations of frost release by hydrophilic surfaces

Zhongliang LIU, Lingyan HUANG, Yujun GOU, Yaomin LIU

期刊论文

Effects of environmental factors on the production and release of matrix-bound phosphine from lake sediments

GENG Jinju, WANG Qiang, WANG Xiaorong, NIU Xiaojun

期刊论文