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糖基化 4

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Occurrence and removal of

Lin WANG,Yongmei LI,Xiaoling SHANG,Jing SHEN

《环境科学与工程前沿（英文）》 2014年第8卷第4期页码 519-530 doi: 10.1007/s11783-013-0610-4

摘要： Six wastewater treatment plants (WWTPs) were investigated to evaluate the occurrence and removal of -nitrosodimethylamine (NDMA), NDMA formation potential (FP) and four specific NDMA precursors, dimethylamine (DMA), trimethylamine (TMA), dimethylformamide (DMFA) and dimethylaminobenzene (DMAB). DMA and tertiary amines with DMA functional group commonly existed in municipal wastewater. Chemically enhanced primary process (CEPP) had no effect on removal of either NDMA or NDMA FP. In WWTPs with secondary treatment processes, considerable variability was observed in the removal of NDMA (19%–85%) and NDMA FP (16%–76%), moreover, there was no definite relationship between the removal of NDMA and NDMA FP. DMA was well removed in all the six surveyed WWTPs; its removal efficiency was greater than 97%. For the removal of tertiary amines, biologic treatment processes with nitrification and denitrification had better removal efficiency than conventional activated sludge process. The best removal efficiencies for TMA, DMFA and DMAB were 95%, 68% and 72%, respectively. CEPP could remove 73% of TMA, 23% of DMFA and 36% of DMAB. After UV disinfection, only 17% of NDMA was removed due to low dosage of UV was applied in WWTP. Although chlorination could reduce NDMA precursors, NDMA concentration was actually increased after chlorination.

关键词： N-nitrosodimethylamine NDMA precursors NDMA formation potential biological treatment process chemically enhanced primary process

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Factors influencing the photodegradation of

Bingbing XU, Zhonglin CHEN, Fei QI, Jimin SHEN, Fengchang WU

《环境科学与工程前沿（英文）》 2009年第3卷第1期页码 91-97 doi: 10.1007/S11783-009-0013-8

摘要： In order to provide basic data for practical application,photodegradation experiment of -nitrosodimethylamine (NDMA) in aqueous solution was carried out with a low-pressure Hg lamp. Effects of the initial concentration of NDMA, solution pH, dissolved oxygen, and the presence of humic acid on NDMA photodegradation were investigated. NDMA at various initial concentrations selected in this study was almost completely photodegraded by UV irradiation within 20 min, except that at 1.07 mmol/L, NDMA could be photodegraded almost completely in the acidic and neutral solutions, while the removal efficiency decreased remarkably in the alkaline solution. Dissolved oxygen enhanced the NDMA photodegradation, and the presence of humic acid inhibited the degradation of NDMA. Depending on the initial concentration of NDMA, NDMA photodegradation by UV obeyed the pseudo-first-order kinetics. Dimethylamine, nitrite, and nitrate were detected as the photodegradation products of NDMA. O was found to be the reactive oxygen species present in the NDMA photodegradation process by UV, based on the inhibiting experiments using tert-butanol and sodium azide.

关键词： N-nitrosodimethylamine (NDMA) ultraviolet irradiation degradation kinetic dimethylamine photodegradation product

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A photolysis coefficient for characterizing the response of aqueous constituents to photolysis

David R. HOKANSON,Ke LI,R. Rhodes TRUSSELL

《环境科学与工程前沿（英文）》 2016年第10卷第3期页码 428-437 doi: 10.1007/s11783-015-0780-3

摘要： UV photolysis and UV based advanced oxidation processes (AOPs) are gaining more and more attention for drinking water treatment. Quantum yield ( ) and molar absorption coefficient ( ) are the two critical parameters measuring the effectiveness of photolysis of a compound. The product of the two was proposed as a fundamental measure of a constituent’s amenability to transformation by photolysis. It was shown that this product, named the photolysis coefficient, , can be determined using standard bench tests and captures the properties that govern a constituent’s transformation when exposed to light. The development showed the photolysis coefficient to be equally useful for microbiological, inorganic and organic constituents. Values of calculated by the authors based on quantum yield and molar absorption coefficient data from the literature were summarized. Photolysis coefficients among microorganisms ranged from 8500 to more than 600000 and are far higher than for inorganic and organic compounds, which varied over a range of approximately 10 to 1000 and are much less sensitive to UV photolysis than the microorganisms.

关键词： UV photolysis disinfection advanced oxidation N-nitrosodimethylamine quantum yield absorption coefficient

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Factors controlling

Chengkun WANG, Xiaojian ZHANG, Chao CHEN, Jun WANG

《环境科学与工程前沿（英文）》 2013年第7卷第2期页码 151-157 doi: 10.1007/s11783-013-0482-7

摘要： The formation of cancinogenic nitrosamines, esp. -nitrosodimethylamine (NDMA) in water and wastewater treatment plants has drawn much attention in recent years. Dissolved organic matter from the transported Luan River water as water source of Tianjin was fractionated with different XAD resins and a series of ultra-filtration membranes with molecular weight (MW) cut-offs of 5k Da, 3k Da, and 1k Da, respectively. The NDMA yields from the raw water and each fraction were measured to investigate their role in NDMA yield. Results indicated that the hydrophilic fraction had a higher NDMA yield than those of hydrophobic fraction and transphilic fraction. The fraction with MW below 1k Da had a higher NDMA yield than that with larger MW. NDMA formation increased as the dissolved organic carbon (DOC) to dissolved organic nitrogen (DON) ratio decreased, which indicated that DON might serve as the real important precursor for NDMA. The correlation between NDMA yield and specific ultraviolet absorbance at 254 nm (SUVA ) suggested that the latter might not represent the specific precursors for NDMA in the water. Besides the water quality, the influences of pH, disinfectant dosage, and disinfection contact time on the formation of NDMA were also examined. These results will help water treatment plants establish measures to control this harmful disinfection by-product.

关键词： N-nitrosodimethylamine (NDMA) disinfection by-product dissolved organic nitrogen (DOC) hydrophilic molecular weight (MW) specific ultraviolet absorbance at 254 nm (SUVA₂₅₄)

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Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿（英文）》 2022年第16卷第10期 doi: 10.1007/s11783-022-1557-0

摘要：

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词： N N-Dimethylformamide Selective catalytic oxidation Cu-ZSM-5 CuO particle size

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Enhancing the efficiency of nitrogen removing bacterial population to a wide range of C:N ratio (1.5:1 to 14:1) for simultaneous C & N removal

《环境科学与工程前沿（英文）》 2022年第16卷第8期 doi: 10.1007/s11783-022-1522-y

摘要：

• Simultaneous C & N removal in Methammox occurs at wide C:N ratio.

关键词： Methanogens Biological Nitrogen Removal (BNR) Simultaneous Methammox C:N ratio

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Effect of fly ash and slag on concrete: Properties and emission analyses

TAM, Khoa N. LE, Ana Catarina Jorge EVANGELISTA, Anthony BUTERA, Cuong N. N. TRAN, Ashraf TEARA

《工程管理前沿（英文）》 2019年第6卷第3期页码 395-405 doi: 10.1007/s42524-019-0019-2

摘要： Recycled concrete is a material with the potential to create a sustainable construction industry. However, recycled concrete presents heterogeneous properties, thereby reducing its applications for some structural purposes and enhancing its application in pavements. This paper provides an insight into a solution in the deformation control for recycled concrete by adding supplementary cementitious materials fly ash and blast furnace slag. Results of this study indicated that the 50% fly ash replacement of Portland cement increased the rupture modulus of the recycled concrete. Conversely, a mixture with over 50% cement replacement by either fly ash or slag or a combination of both exhibited detrimental effect on the compressive strength, rupture modulus, and drying shrinkage. The combined analysis of environmental impacts and mechanical properties of recycled concrete demonstrated the possibility of optimizing the selection of recycled concrete because the best scenario in this study was obtained with the concrete mixture M8 (50% of fly ash+ 100% recycled coarse aggregate).

关键词： recycled aggregate recycled concrete fly ash and slag

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Endemicity of H9N2 and H5N1 avian influenza viruses in poultry in China poses a serious threat to poultry

Jiao HU,Xiufan LIU

《农业科学与工程前沿（英文）》 2016年第3卷第1期页码 11-24 doi: 10.15302/J-FASE-2016092

摘要： The H9N2 and H5N1 avian influenza viruses (AIVs) have been circulating in poultry in China and become endemic since 1998 and 2004, respectively. Currently, they are prevalent in poultry throughout China. This endemicity makes them actively involved in the emergence of the novel lineages of other subtypes of influenza viruses, such as the well-known viruses of the highly pathogenic avian influenza (HPAI) H5N2 and the 2013 novel H7N7, H7N9 and H10N8 subtypes, thereby threatening both the poultry industry and public health. Here, we will review briefly the prevalence and evolution, pathogenicity, transmission, and disease control of these two subtypes and also discuss the possibility of emergence of potentially virulent and highly transmissible AIVs to humans.

关键词： avian influenza virus H9N2 H5N1 novel viruses public health

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CO, N, and CO/N mixed gas injection for enhanced shale gas recovery and CO geological storage

《能源前沿（英文）》 2023年第17卷第3期页码 428-445 doi: 10.1007/s11708-023-0865-9

摘要： In this work, using fractured shale cores, isothermal adsorption experiments and core flooding tests were conducted to investigate the performance of injecting different gases to enhance shale gas recovery and CO₂ geological storage efficiency under real reservoir conditions. The adsorption process of shale to different gases was in agreement with the extended-Langmuir model, and the adsorption capacity of CO₂ was the largest, followed by CH_4, and that of N₂ was the smallest of the three pure gases. In addition, when the CO₂ concentration in the mixed gas exceeded 50%, the adsorption capacity of the mixed gas was greater than that of CH₄, and had a strong competitive adsorption effect. For the core flooding tests, pure gas injection showed that the breakthrough time of CO₂ was longer than that of N₂, and the CH₄ recovery factor at the breakthrough time (

R C H 4

) was also higher than that of N₂. The

R C H 4

of CO₂ gas injection was approximately 44.09%, while the

R C H 4

of N₂ was only 31.63%. For CO₂/N₂ mixed gas injection, with the increase of CO₂ concentration, the

R C H 4

increased, and the

R C H 4

for mixed gas CO₂/N₂ = 8:2 was close to that of pure CO₂, about 40.24%. Moreover, the breakthrough time of N₂ in mixed gas was not much different from that when pure N₂ was injected, while the breakthrough time of CO₂ was prolonged, which indicated that with the increase of N₂ concentration in the mixed gas, the breakthrough time of CO₂ could be extended. Furthermore, an abnormal surge of N₂ concentration in the produced gas was observed after N₂ breakthrough. In regards to CO₂ storage efficiency (

S s t o r a g e - C O 2

), as the CO₂ concentration increased,

S s t o r a g e - C O 2

also increased. The

S s t o r a g e - C O 2

of the pure CO₂ gas injection was about 35.96%, while for mixed gas CO₂/N₂ = 8:2,

S s t o r a g e - C O 2

was about 32.28%.

关键词： shale gas gas injection competitive adsorption enhanced shale gas recovery CO₂ geological storage

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The performance of nitrate-reducing Fe(II) oxidation processes under variable initial Fe/N ratios: The

《环境科学与工程前沿（英文）》 2021年第15卷第4期 doi: 10.1007/s11783-020-1366-2

摘要：

•Bacterially-mediated coupled N and Fe processes examined in incubation experiments.

关键词： Denitrification N₂O emission Fe(II) oxidation Fe/N ratio Fe minerals

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N95口罩重复使用

Dana Mackenzie

《工程（英文）》 2020年第6卷第6期页码 593-596 doi: 10.1016/j.eng.2020.04.003

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Physiological functions and clinical implications of the N-end rule pathway

null

《医学前沿（英文）》 2016年第10卷第3期页码 258-270 doi: 10.1007/s11684-016-0458-7

摘要：

The N-end rule pathway is a unique branch of the ubiquitin-proteasome system in which the determination of a protein’s half-life is dependent on its N-terminal residue. The N-terminal residue serves as the degradation signal of a protein and thus called N-degron. N-degron can be recognized and modifed by several steps of post-translational modifications, such as oxidation, deamination, arginylation or acetylation, it then polyubiquitinated by the N-recognin for degradation. The molecular basis of the N-end rule pathway has been elucidated and its physiological functions have been revealed in the past 30 years. This pathway is involved in several biological aspects, including transcription, differentiation, chromosomal segregation, genome stability, apoptosis, mitochondrial quality control, cardiovascular development, neurogenesis, carcinogenesis, and spermatogenesis. Disturbance of this pathway often causes the failure of these processes, resulting in some human diseases. This review summarized the physiological functions of the N-end rule pathway, introduced the related biological processes and diseases, with an emphasis on the inner link between this pathway and certain symptoms.

关键词： N-end rule pathway Ate1 cardiovascular development neurogenesis spermatogenesis neurodegenerative disorders Johanson–Blizzard syndrome

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Planet position errors in planetary transmission: Effect on load sharing and transmission error

Miguel IGLESIAS, Alfonso FERNáNDEZ, Ana DE-JUAN, Ramón SANCIBRIáN, Pablo GARCíA

《机械工程前沿（英文）》 2013年第8卷第1期页码 80-87 doi: 10.1007/s11465-013-0362-7

摘要：

In this paper an advanced model of spur gear transmissions developed by the authors is used to study the influence of carrier planet pin hole position errors on the behaviour of the transmission. The model, initially conceived for external gear modeling, has been extended with internal meshing features, and thus increasing its capabilities to include planetary transmission modeling. The new features are presented, along with the summary of the model general approach. The parameters and characteristics of the planetary transmission used in the paper are introduced. The influence of carrier planet pin hole position errors on the planet load sharing is studied, and several static cases are given as examples in order to show the ability of the model. Tangential and radial planet pin hole position errors are considered independently, and the effect of the load level is also taken into account. It is also given attention to the effect on the transmission error of the transmission. Two different configurations for the planetary transmission are used, attending to the fixed or floating condition of the sun, and the differences in terms of load sharing ratio are shown.

关键词： gear planetary epicyclic transmission load sharing transmission error

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Production of N

Youkui GONG,Yongzhen PENG,Shuying WANG,Sai WANG

《环境科学与工程前沿（英文）》 2014年第8卷第4期页码 589-597 doi: 10.1007/s11783-013-0571-7

摘要： The N O production in two nitrogen removal processes treating domestic wastewater was investigated in laboratory-scale aerobic-anoxic sequencing batch reactors (SBRs). Results showed that N O emission happened in the aerobic phase rather than in the anoxic phase. During the aerobic phase, the nitrogen conversion to N O gas was 27.7% and 36.8% of loss for conventional biologic N-removal process and short-cut biologic N-removal process. The dissolved N O was reduced to N in the anoxic denitrification phase. The N O production rate increased with the increasing of nitrite concentration and ceased when oxidation was terminated. Higher nitrite accumulation resulted in higher N O emission in the short-cut nitrogen removal process. Pulse-wise addition of 20 mg gave rise to 3-fold of N O emission in the conventional N-removal process, while little change happened with 20 mg was added to SBR1.

关键词： conventional N-removal process N₂O short-cut N-removal process nitrite accumulation ammonia- oxidizing bacteria (AOB) denitrification

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A highly efficient methodology for the preparation of

Yongxin Zhang, Shucheng Wang, Yaodong Huang

《化学科学与工程前沿（英文）》 2021年第15卷第3期页码 679-686 doi: 10.1007/s11705-020-1979-9

摘要： A convenient and highly efficient method is described for the synthesis of -methoxycarbazole derivatives, including those with sterically demanding, benzannulated, or strongly electron-donating or -withdrawing substituents. Various -methoxycarbazole derivatives were directly prepared in good-to-moderate yields by the Pd (dba) CHCl /9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene-catalyzed reactions of the corresponding dibromobiphenyl compounds and methoxya-mine. Based on this methodology, the first total synthesis of 3,3′-[oxybis(methylene)]bis(9-methoxy-9 -carbazole), an antimicrobial dimeric carbazole alkaloid previously isolated from the stem bark of , was achieved in 18% yield over seven steps from 1,2-dibromobenzene.

关键词： N-methoxyl carbazole dimeric N-methoxyl carbazole alkaloid total synthesis double N-arylation of methoxyamine