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Design of tandem genes cluster for isoflavone engineering

Xunli XIA PhD , Guangxiao YANG PhD , Guangyuan HE PhD ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 292-296 doi: 10.1007/s11684-009-0057-y

摘要： In this paper, a universal effective novel method of constructing tandem genes cluster for isoflavone engineering was reported. A tandem genes cluster () of secondary metabolites of plant isoflavones was constructed by using the chalcone synthase (CHS), chalcone isomerase (CHI), and isoflavone synthase (IFS) (GenBank accession numbers EU526827, EU526829, EU526830) in only one recombination with the pET22b vector. The resulting expression vector pET- was heterogeneously expressed and co-incubated with barrenwort extractions, and the genistein-like component was detected.

关键词： isoflavones engineering     secondary metabolism     tandem genes cluster    

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Alluvial channel hydrodynamics around tandem piers with downward seepage

Rutuja CHAVAN, Wenxin HUAI, Bimlesh KUMAR

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1445-1461 doi: 10.1007/s11709-020-0648-x

摘要： In this paper, we report the turbulent flow structures and the scour geometry around two piers with different diameters. An experiment was conducted on a non-uniform sand bed with two types of tandem arrangements, namely, pier (T1) with a 75 mm front and 90 mm rear, and pier (T2) with a 90 mm front and 75 mm rear, with and without-seepage flows, respectively. A strong wake region was observed behind the piers, but the vortex strength diminished with downward seepage. Streamwise velocity was found to be maximum near the bed downstream of the piers and at the edge of the scour hole upstream of the piers. Quadrant analysis was used to recognize the susceptible region for sediment entrainment and deposition. Upstream of the piers near the bed, the moments, turbulent kinetic energy (TKE), and TKE fluxes were found to decrease with downward seepage, in contrast to those in a plane mobile bed without piers. The reduction percentages of scour depth at the rear pier compared with the front one were approximately 40% for T1 and 60% for T2. Downward seepage also resulted in restrained growth of scouring with time.

关键词： scour     seepage     Strouhal number     tandem arrangement     turbulent characteristics    

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Understanding high-emitting households in the UK through a cluster analysis

Xinfang WANG, Ming MENG

《能源前沿（英文）》 2019年 第13卷 第4期   页码 612-625 doi: 10.1007/s11708-019-0647-6

摘要： Anthropogenic climate change is a global problem that affects every country and each individual. It is largely caused by human beings emitting greenhouse gases into the atmosphere. In general, a small percentage of the population is responsible for a large amount of emissions. This paper focuses on high emitters and their CO emissions from energy use in UK homes. It applies a cluster approach, aiming to identify whether the high emitters comprise clusters where households in each cluster share similar characteristics but are different from the others. The data are mainly based on the Living Cost and Food survey in the UK. The results show that after equivalising both household emissions and income, the high emitters can be clustered into six groups which share similar characteristics within each group, but are different from the others in terms of income, age, household composition, category and size of the dwelling, and tenure type. The clustering results indicate that various combinations of socioeconomic factors, such as low-income single female living in an at least six-room property, or high-income retired couple owning a large detached house, could all lead to high CO emissions from energy use at home. Policymakers should target each high-emitter cluster differently to reduce CO emissions from energy consumption at home more effectively.

关键词： cluster analysis     emissions reduction     energy use     high emitters     household energy consumption     socioeconomic factors    

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Available energy analysis of new tandem double-capillary tube refrigeration system for refrigerator-freezers

HE Maogang, ZHANG Ying, SONG Xinzhou, ZHANG Jiantao

《能源前沿（英文）》 2008年 第2卷 第1期   页码 36-42 doi: 10.1007/s11708-008-0013-6

摘要： A new tandem double-capillary tube refrigeration system for refrigerator-freezers is proposed. A capillary tube was added between the two evaporators in the fresh and frozen food storage chests to raise the evaporation temperature of the refrigerating chamber, and reduce the heat exchange temperature difference and the available energy loss. Peng-Robinson (P-R) equation of state was adopted to calculate the thermodynamic properties of the refrigerants, and the available energy analysis of the vapor compression refrigeration cycle was programmed to calculate the thermodynamic performances of the new and the conventional refrigeration cycle of the refrigerator-freezer. The calculation results show that the available energy efficiency of the conventional refrigeration cycle of the refrigerator-freezer is 21.20% and 20.57%, respectively when the refrigerant is R12 and R134a, while that of the double-capillary tube refrigeration cycle of the refrigerator-freezer is 23.97% and 23.44%, respectively. By comparison, the available energy efficiency of the new refrigeration system increases by 13.07% and 13.95%, respectively.
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Scaling up of cluster beam deposition technology for catalysis application

《化学科学与工程前沿（英文）》 2021年 第15卷 第6期   页码 1360-1379 doi: 10.1007/s11705-021-2101-7

摘要： Many research works have demonstrated that the combination of atomically precise cluster deposition and theoretical calculations is able to address fundamental aspects of size-effects, cluster-support interactions, and reaction mechanisms of cluster materials. Although the wet chemistry method has been widely used to synthesize nanoparticles, the gas-phase synthesis and size-selected strategy was the only method to prepare supported metal clusters with precise numbers of atoms for a long time. However, the low throughput of the physical synthesis method has severely constrained its wider adoption for catalysis applications. In this review, we introduce the latest progress on three types of cluster source which have the most promising potential for scale-up, including sputtering gas aggregation source, pulsed microplasma cluster source, and matrix assembly cluster source. While the sputtering gas aggregation source is leading ahead with a production rate of ~20 mg·h–1, the pulsed microplasma source has the smallest physical dimensions which makes it possible to compact multiple such devices into a small volume for multiplied production rate. The matrix assembly source has the shortest development history, but already show an impressive deposition rate of ~10 mg·h–1. At the end of the review, the possible routes for further throughput scale-up are envisaged.

关键词： nanoparticle     cluster     cluster beam deposition     magnetron sputtering     heterogeneous catalysis    

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Metagenomic analysis on resistance genes in water and microplastics from a mariculture system

《环境科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 4-4 doi: 10.1007/s11783-021-1438-y

摘要：

Microplastics existing widely in different matrices have been regarded as a reservoir for emerging contaminants. Mariculture systems have been observed to host microplastics and antibiotic resistance genes (ARGs). However, more information on proliferation of ARGs and metal resistance genes (MRGs) in mariculture system at the presence of microplastics is needed.

关键词： Antibiotic resistance genes     Metal resistance genes     Metagenomic analysis     Microplastics     Mariculture    

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quantification of several classes of antibiotics in water, sediments, and fish muscles by liquid chromatography–tandem

WEI Yimei,ZHANG Yuan,XU Jian,GUO Changsheng,LI Lei,FAN Wenhong

《环境科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 357-371 doi: 10.1007/s11783-013-0580-6

摘要： Precise and sensitive methods for the simultaneous determination of different classes of antibiotics, including sulphonamides, fluoroquinolones, macrolides, tetracyclines, and trimethoprim in surface water, sediments, and fish muscles were developed. In water samples, drugs were extracted with solid-phase extraction (SPE) by passing 1000 mL of water through hydrophilic lipophilic balanced (HLB) SPE cartridges. Sediment samples were solvent-extracted, followed by tandem SPE (strong anion exchange (SAX) + HLB) clean-ups. Fish muscles were extracted by a mixture of acetonitrile and citric buffer (80:20, v/v) solution, and cleaned by SPE. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) with multiple reaction monitoring (MRM) detection was employed to quantify all compounds. The recoveries for the antibiotics in the spiked water, sediment, and fish samples were 60.2%–95.8%, 48.1%–105.3%, and 59.8%–103.4%, respectively. The methods were applied to samples taken from Dianchi Lake, China. It showed that concentrations of the detected antibiotics ranged from limits of quantification (LOQ) to 713.6 ng·L (ofloxacin) in surface water and from less than LOQ to 344.8 μg·kg (sulphamethoxazole) in sediments. The number of detected antibiotics and the overall antibiotic concentrations were higher in the urban area than the rural area, indicating the probable role of livestock and human activities as important sources of antibiotic contamination. In fish muscles, the concentration of norfloxacin was the highest (up to 38.5 μg·kg ), but tetracyclines and macrolides were relatively low. Results showed that the methods were rapid and sensitive, and capable of determining several classes of antibiotics from each of the water, sediment, and fish matrices in a single run.

关键词： antibiotics     liquid chromatography–tandem mass spectrometry (LC-MS/MS)     water     sediment     fish muscle    

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Distribution and removal of antibiotic resistance genes during anaerobic sludge digestion with alkaline

Mengli Wang, Ruying Li, Qing Zhao

《环境科学与工程前沿（英文）》 2019年 第13卷 第3期 doi: 10.1007/s11783-019-1127-2

摘要：

Sludge digestion is critical to control the spread of ARGs from wastewater to soil.

Fate of ARGs in three pretreatment-AD processes was investigated.

UP was more efficient for ARGs removal than AP and THP in pretreatment-AD process.

The total ARGs concentration showed significant correlation with 16S rRNA gene.

The bacteria carrying ARGs could be mainly affiliated with Proteobacteria.

关键词： Tetracycline resistance genes     Sulfonamide resistance genes     16S rRNA gene     Sludge pretreatment     Anaerobic sludge digestion    

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Environmental effects and risk control of antibiotic resistance genes in the organic solid waste aerobic

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1415-5

摘要：

• ARGs were detected in livestock manure, sludge, food waste and fermentation dregs.

关键词： Antibiotic resistance genes     Organic solid waste     Aerobic composting     Livestock manure     Sludge    

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water using liquid-liquid microextraction coupled with gas chromatography—positive chemical ionization-tandem

Jian LU,Paul S. WILLS,P. CHRIS WILSON

《环境科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 477-481 doi: 10.1007/s11783-015-0820-z

摘要： A rapid, inexpensive and laboratory friendly method was developed for analysis of off-flavor/odor compounds in fresh and salt water using gas chromatography with chemical ionization-tandem mass spectrometry. Off-flavor/odor compounds included geosmin, 2-methylisoborneol (MIB), 2-isobutyl-3-methyoxypyrazine (IBMP), and 2-isopropyl-3-methoxypyrazine (IPMP). Using this method, a single sample can be extracted within minutes using only 1 mL of organic solvent. The ion transitions for IPMP, IBMP, MIB, and geosmin were 153>121, 167>125, 152>95, and 165>109, respectively. The linearity of this method for analyzing MIB ranged from 4 to 200 ng·L , and from 0.8 to 200 ng·L for the other analytes. Method recoveries ranged from 97% to 111% and percent relative standard deviations ranged from 3% to 9%, indicating that the method is accurate, precise, and reliable.

关键词： off-flavor/odor compounds     liquid-liquid microextraction     gas chromatography-tandem mass spectrometry    

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ultraviolet/chlorine process on microbial community structure, typical pathogens, and antibiotic resistance genes

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1521-z

摘要：

• UV/chlorine can effectively remove VBNC pathogens, ARGs and MGEs in reclaimed water.

关键词： UV/chlorine process     Pathogen     Antibiotic resistance genes     High-throughput qPCR     Reclaimed water    

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圆锥滚子轴承振动的灰色模糊聚类分析

刘劲军,夏新涛,张立红

《中国工程科学》 2008年 第10卷 第7期   页码 112-117

摘要：

以30204型圆锥滚子轴承试验数据为基础，利用灰色模糊聚类分析方法对影响圆锥滚子轴承振动的 因素进行了综合分析，将圆锥滚子轴承各项参数按其对振动的影响分为三类：第一类对振动的影响最大，其 中包括滚子凸度、滚子直径偏差Dw 等参数；第二类对振动的影响较大，其中包括内滚道圆度，内滚道直线性 Li 等参数；第三类对振动的影响最小，其中包括内滚道波纹度，内滚道的角度偏差Δ２β 等参数。根据分类可 知，试验中圆锥滚子轴承的大部分参数都会对振动产生较大的影响。

关键词： 圆锥滚子轴承     振动     灰色模糊聚类分析    

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Distribution of antibiotic resistance genes and their association with bacteria and viruses in decentralized

《环境科学与工程前沿（英文）》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1469-4

摘要：

• Distribution of ARGs in decentralized sewage facilities were investigated.

关键词： Decentralized sewage treatment facilities     Antibiotic resistance genes     Virus     Metagenomics     Network analysis    

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Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

《能源前沿（英文）》   页码 782-795 doi: 10.1007/s11708-023-0905-8

摘要： China is vigorously promoting the “whole county promotion” of distributed photovoltaics (DPVs). However, the high penetration rate of DPVs has brought problems such as voltage violation and power quality degradation to the distribution network, seriously affecting the safety and reliability of the power system. The traditional centralized control method of the distribution network has the problem of low efficiency, which is not practical enough in engineering practice. To address the problems, this paper proposes a cluster voltage control method for distributed photovoltaic grid-connected distribution network. First, it partitions the distribution network into clusters, and different clusters exchange terminal voltage information through a “virtual slack bus.” Then, in each cluster, based on the control strategy of “reactive power compensation first, active power curtailment later,” it employs an improved differential evolution (IDE) algorithm based on Cauchy disturbance to control the voltage. Simulation results in two different distribution systems show that the proposed method not only greatly improves the operational efficiency of the algorithm but also effectively controls the voltage of the distribution network, and maximizes the consumption capacity of DPVs based on qualified voltage.

关键词： distributed photovoltaics (DPVs)     cluster partitioning     improved differential evolution algorithm     voltage control     consumption capacity of distributed photovoltaics    

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Research progress in pathogenic genes of hereditary non-syndromic mid-frequency deafness

null

《医学前沿（英文）》 2016年 第10卷 第2期   页码 137-142 doi: 10.1007/s11684-016-0449-8

摘要：

Hearing impairment is considered as the most prevalent impairment worldwide. Almost 600 million people in the world suffer from mild or moderate hearing impairment, an estimated 10% of the human population. Genetic factors play an important role in the pathogenesis of this disorder. Hereditary hearing loss is divided into syndromic hearing loss (associated with other anomalies) and non-syndromic hearing loss (not associated with other anomalies). Approximately 80% of genetic deafness is non-syndromic. On the basis of the frequency of hearing loss, hereditary non-syndromic hearing loss can be divided into high-, mid-, low-, and total-frequency hearing loss. An audiometric finding of mid-frequency sensorineural hearing loss, or a “bowl-shaped” audiogram, is uncommon. Up to now, merely 7 loci have been linked to mid-frequency hearing loss. Only four genetic mid-frequency deafness genes, namely, DFNA10 (EYA4), DFNA8/12 (TECTA), DFNA13 (COL11A2), DFNA44 (CCDC50), have been reported to date. This review summarizes the research progress of the four genes to draw attention to mid-frequency deafness genes.

关键词： hereditary non-syndromic hearing loss     mid-frequency hearing loss     deafness genes    

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标题 作者 时间 类型 操作

Design of tandem genes cluster for isoflavone engineering

Xunli XIA PhD , Guangxiao YANG PhD , Guangyuan HE PhD ,

期刊论文

Alluvial channel hydrodynamics around tandem piers with downward seepage

Rutuja CHAVAN, Wenxin HUAI, Bimlesh KUMAR

期刊论文

Understanding high-emitting households in the UK through a cluster analysis

Xinfang WANG, Ming MENG

期刊论文

Available energy analysis of new tandem double-capillary tube refrigeration system for refrigerator-freezers

HE Maogang, ZHANG Ying, SONG Xinzhou, ZHANG Jiantao

期刊论文

Scaling up of cluster beam deposition technology for catalysis application

期刊论文

Metagenomic analysis on resistance genes in water and microplastics from a mariculture system

期刊论文

quantification of several classes of antibiotics in water, sediments, and fish muscles by liquid chromatography–tandem

WEI Yimei,ZHANG Yuan,XU Jian,GUO Changsheng,LI Lei,FAN Wenhong

期刊论文

Distribution and removal of antibiotic resistance genes during anaerobic sludge digestion with alkaline

Mengli Wang, Ruying Li, Qing Zhao

期刊论文

Environmental effects and risk control of antibiotic resistance genes in the organic solid waste aerobic

期刊论文

water using liquid-liquid microextraction coupled with gas chromatography—positive chemical ionization-tandem

Jian LU,Paul S. WILLS,P. CHRIS WILSON

期刊论文

ultraviolet/chlorine process on microbial community structure, typical pathogens, and antibiotic resistance genes

期刊论文

圆锥滚子轴承振动的灰色模糊聚类分析

刘劲军,夏新涛,张立红

期刊论文

Distribution of antibiotic resistance genes and their association with bacteria and viruses in decentralized

期刊论文

Cluster voltage control method for “Whole County” distributed photovoltaics based on improved differential

期刊论文

Research progress in pathogenic genes of hereditary non-syndromic mid-frequency deafness

null

期刊论文