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Effect of pH on biologic degradation of

Hongjing LI, Mengli HAO, Jingxian LIU, Chen CHEN, Zhengqiu FAN, Xiangrong WANG

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 224-230 doi: 10.1007/s11783-011-0314-6

摘要： In this paper, the effect of pH on biological degradation of by alga-lysing bacteria in laboratory-scale sequencing batch biofilm reactors (SBBRs) was investigated. After 10 d filming with waste activated sludge, the biological film could be formed, and the bioreactors in which laid polyolefin resin filler were used to treat algal culture. By comparing the removal efficiency of chlorophyll at different aerobic time, the optimum time was determined as 5 h. Under pH 6.5, 7.5, and 8.5 conditions, the removal rates of were respectively 75.9%, 83.6%, and 78.3% (in term of chlorophyll ), and that of Chemical Oxygen Demand (COD ) were 30.6%, 35.8%, and 33.5%. While the removal efficiencies of ammonia nitrogen ( ) were all 100%. It was observed that the sequence of the removal efficiencies of algae, and organic matter were pH 7.5>pH 8.5>pH 6.5. The results showed that the dominant alga-lysing bacteria in the SBBRs was strain HM-01, which was identified as sp. by Polymerase Chain Reaction (PCR) amplification of the 16S rRNA gene, Basic Local Alignment Search Tool (BLAST) analysis, and comparison with sequences in the GenBank nucleotide database. The algicidal activated substance which HM-01 strain excreted could withstand high temperature and pressure, also had better hydrophily and stronger polarity.

关键词： pH     biological degradation     alga-lysing bacteria     sequencing batch biofilm reactor (SBBR)     16S rRNA     Bacillus sp    

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Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production: effectof pH at ambient temperature

Leiyu FENG, Yuanyuan YAN, Yinguang CHEN

《环境科学与工程前沿（英文）》 2011年 第5卷 第4期   页码 623-632 doi: 10.1007/s11783-011-0334-2

摘要： Effect of pH ranging from 4.0 to 11.0 on co-fermentation of waste activated sludge (WAS) with food waste for short-chain fatty acids (SCFAs) production at ambient temperature was investigated in this study. Experimental results showed that the addition of food waste significantly improved the performance of WAS fermentation system, which resulted in the increases of SCFAs production and substrate reduction. The SCFAs production at pH 6.0, 7.0, 8.0, and 9.0 and fermentation time of 4 d was respectively 5022.7, 6540.5, 8236.6, and 7911.7 mg COD·L , whereas in the blank tests (no pH adjustment, pH 8.0 (blank test 1), no food waste addition, pH 8.0 (blank test 2), and no WAS addition (blank test 3)) it was only 1006.9, 971.1, and 1468.5 mg COD·L , respectively. The composition of SCFAs at pH from 6.0 to 9.0 was also different from other conditions and propionic acid was the most prevalent SCFA, which was followed by acetic and n-butyric acids, while acetic acid was the top product under other conditions. At pH 8.0 a higher volatile suspended solids (VSS) reduction of 16.6% for the mixture of WAS and food waste than the sole WAS indicated a synergistic effect existing in fermentation system with WAS and food waste. The influence of pH on the variations of nutrient content was also studied during anaerobic fermentation of the mixture of WAS and food waste at different pH conditions. The release of increased with fermentation time at all pH values investigated except 4.0, 5.0 and in blank test one. The concentrations of soluble phosphorus at acidic pHs and in the blank test one were higher than those obtained at alkaline pHs. Ammonia and phosphorus need to be removed before the SCFAs-enriched fermentation liquid from WAS and food waste was used as the carbon source.

关键词： waste activated sludge (WAS)     food waste     co-fermentation     short-chain fatty acids (SCFAs)     pH     synergistic effect    

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The effect of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between

Asghar Azizi, Seid Ziaoddin Shafaei, Mohammad Noaparast, Mohammad Karamoozian

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 464-471 doi: 10.1007/s11705-013-1356-z

摘要： The role of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between chalcopyrite and pyrite and low alloy steel balls were investigated in the grinding of Sarcheshmeh porphyry copper sulfide ore. All these factors strongly affect the galvanic current between the minerals and the steel during the grinding process. The galvanic current density decreased as the solution pH and percent solids increased. In addition, changing the water in the ball mill from tap to distilled water reduced the galvanic current between the minerals and the balls. Potentiodynamic polarization curves showed that pyrite and chalcopyrite demonstrated typical active-passive-transpassive anodic behavior in the grinding of copper ore. However, the nature of their transitions from the active to the passive state differed. This behavior was not seen in the grinding of pure minerals. In addition, an EDTA extraction technique was employed to quantify the amount of oxidized iron in the mill discharge. The amount of extractable iron was influenced by the same experimental factors and in the same way as the galvanic current.

关键词： steel ball     galvanic interaction     pyrite     chalcopyrite     polarization curves    

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4-Amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomalcellular imaging agents: The effect of substituent patterns on PET directional quenching

Miguel Martínez-Calvo, Sandra A. Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

《化学科学与工程前沿（英文）》 2020年 第14卷 第1期   页码 61-75 doi: 10.1007/s11705-019-1862-8

摘要： Four new fluorescent sensors ( - ) based on the 4-amino-1,8-naphthalimide fluorophores ( ) have been synthesized based on the classical fluorophore-spacer-receptor model. These four compounds all gave rise to emission bands centred at 535 nm, which were found to be highly pH dependent, the emission being ‘switched on’ in acidic media, while being quenched due to PET from the amino moieties to the excited state of the at more alkaline pH. The luminescent pH dependence for these probes was found to be highly dependent on the substitution on the imide site, as well as the polyamine chain attached to the position 4-amino moiety. In the case of sensor the presence of the 4-amino-aniline dominated the pH dependent quenching. Nevertheless, at higher pH, PET quenching was also found to occur from the polyamine site. Hence, is better described as a receptor -spacer -fluorophore-spacer -receptor system, where the dominant PET process is due to (normally less favourable) ‘directional’ PET quenching from the 4-amino-aniline unit to the site. Similar trends and pH fluorescence dependences were also seen for and . These compounds were also tested for their imaging potential and toxicity against HeLa cells (using DRAQ5 as nuclear stain which does now show pH dependent changes in acidic and neutral pH) and the results demonstrated that these compounds have reduced cellular viability at moderately high concentrations (with IC values between ca. 8‒30 µmol∙L ), but were found to be suitable for intracellular pH determination at 1 µmol∙L concentrations, where no real toxicity was observed. This allowed us to employ these as lysosomal probes at sub-toxic concentrations, where the based emission was found to be pH depended, mirroring that seen in aqueous solution for , with the main fluorescence changes occurring within acidic to neutral pH.

关键词： sensors     pH     photoinduced electron transfer     cellular imaging     confocal microscopy    

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Effect of protein on PVDF ultrafiltration membrane fouling behavior under different pH conditions: interface

Xudong WANG,Miao ZHOU,Xiaorong MENG,Lei WANG,Danxi HUANG

《环境科学与工程前沿（英文）》 2016年 第10卷 第4期 doi: 10.1007/s11783-016-0855-9

摘要： pH values of the BSA solution significantly impact the process of membrane fouling. Dramatic flux decline is caused by membrane–BSA adhesion force at start of filtration. XDLVO theory shows the polar or Lewis acid–base interaction plays a major role in membrane fouling. To further determine the fouling behavior of bovine serum albumin (BSA) on different hydrophilic PVDF ultrafiltration (UF) membranes over a range of pH values, self-made atomic force microscopy (AFM) colloidal probes were used to detect the adhesion forces of membrane–BSA and BSA–BSA, respectively. Results showed that the membrane–BSA adhesion interaction was stronger than the BSA–BSA adhesion interaction, and the adhesion force between BSA–BSA-fouled PVDF/PVA membranes was similar to that between BSA–BSA-fouled PVDF/PVP membranes, which indicated that the fouling was mainly caused by the adhesion interaction between membrane and BSA. At the same pH condition, the PVDF/PVA membrane–BSA adhesion force was smaller than that of PVDF/PVP membrane–BSA, which illustrated that the more hydrophilic the membrane was, the better antifouling ability it had. The extended Derjaguin–Landau–Verwey–Overbeek (XDLVO) theory predicts that the polar or Lewis acid–base (AB) interaction played a dominant role in the interfacial free energy of membrane–BSA and BSA–BSA that can be affected by pH. For the same membrane, the pH values of a BSA solution can have a significant impact on the process of membrane fouling by changing the AB component of free energy.

关键词： PVDF membrane     Membrane fouling     Adhesion force     Protein     Interfacial free energy    

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Effect of environment change on the strength of cement/lime treated clays

Takenori HINO, Rui JIA, Seiji SUEYOSHI, Tri HARIANTO

《结构与土木工程前沿（英文）》 2012年 第6卷 第2期   页码 153-165 doi: 10.1007/s11709-012-0153-y

摘要： The field strengths of cement/lime treated clays were investigated in the Ariake Sea costal lowlands. The deposition environment of the investigation location is reconstructed and compared to the present ground environment. The mechanism of the ground environment change and its effect on the strength of cement/lime treated soil are discussed. The strength development of improved soil using cement and lime in different curing environments was investigated in the laboratory for studying the effect of environment change on the strength also. It has been found that the strength deterioration of improved soil in deep mixing method is due to 1) the ground environment change due to the secondary oxidation which results in low pH value and high organic content, and 2) the formations of the porous structures result from the elution of the calcium ions. Also, it has been found that the initial strength increase of the improved soil is related to the dissolved silica and that the dissolution of the silica in clay minerals needs long time. When examining the long-term strength for preventing strength degradation, the effect of environmental change has to be considered. The importance of measuring pH and oxidation-reduction potential (ORP) of the ground for cement/lime solidification method is explained.

关键词： soil solidification     ground environment     strength deterioration     pH     oxidation-reduction potential (ORP)     silica    

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Co-present Pb(II) accelerates the oxidation of organic contaminants by permanganate: Role of Pb(III)

《环境科学与工程前沿（英文）》 2022年 第16卷 第8期 doi: 10.1007/s11783-022-1530-y

摘要：

• Simultaneous removal of organic contaminants and Pb(II) was achieved by Mn(VII).

关键词： Permanganate     Pb(II) oxidation     MnO2     pH effect    

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Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

《化学科学与工程前沿（英文）》 2023年 第17卷 第3期   页码 298-306 doi: 10.1007/s11705-022-2212-9

摘要： Herein, a reversible pH fluorescent sensor was developed using caffeic acid as the precursor by one-step solvothermal synthesis method. The carbon dots-based sensor (CA-CDs) exhibited pH-dependent increase in fluorescence intensity and showed linear relationship in the range of pH 6.60 and 8.00. Notably, the fluorescence sensor has a reversible response to pH change. Finally, the CA-CDs has been successfully applied for two-photon imaging of the pH in liver and kidney of diabetic mice. Imaging results showed that the pH value in kidney of diabetic mice was lower than that of the normal mice, while the pH value in liver of diabetic mice was almost the same as that of the normal mice. The present study provides a simple analytical method for pH detection suitable for in vivo.

关键词： carbon dots     two-photon imaging     pH     diabetic mice    

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NO oxidation over Co-La catalysts and NO

Tiejun Zhang,Jian Li,Hong He,Qianqian Song,Quanming Liang

《环境科学与工程前沿（英文）》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0906-x

摘要： The Co-La catalyst (pH= 1) exhibited maximum NO conversion of 43% at 180°C. Acid modified catalyst enhanced the resistance to SO . The formed sulfates may block the pore structure of the catalyst. The NO conversion of compact SCR was 91% at 180°C at the highest space velocity. A series of Co-La catalysts were prepared using the wet impregnation method and the synthesis of catalysts were modified by controlling pH with the addition of ammonium hydroxide or oxalic solution. All the catalysts were systematically investigated for NO oxidation and SO resistance in a fixed bed reactor and were characterized by Brunanuer–Emmett–Teller (BET) method, Fourier Transform infrared spectroscopy (FTIR), X–ray diffraction (XRD), Thermogravimetric (TG) and Ion Chromatography (IC). Among the catalysts, the one synthesized at pH= 1 exhibited the maximum NO conversion of 43% at 180°C. The activity of the catalyst was significantly suppressed by the existence of SO (300 ppm) at 220°C. Deactivation may have been associated with the generation of cobalt sulfate, and the SO adsorption quantity of the catalyst might also have effected sulfur resistance. In the case of the compact selective catalytic reduction (SCR), the activity increased from 74% to 91% at the highest gas hourly space velocity (GHSV) of 300000 h when the NO catalyst maintained the highest activity, in excess of 50% more than that of the standard SCR.

关键词： NO catalytic oxidation     pH effect     Low temperature     Sulfur dioxide     High space velocity     SCR    

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Effect of succinic acid deamidation-induced modification on wheat gluten

Lan LIAO, Mouming ZHAO, Haifeng ZHAO, Jiaoyan REN, Chun CUI, Xiao HU,

《化学科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 386-392 doi: 10.1007/s11705-009-0250-1

摘要： The effect of succinic acid deamidation-induced modification on wheat gluten was investigated in the present study. The changes of surface hydrophobicity, functional properties, secondary structure, and sensibility of proteolysis of modified samples were determined. The solubility of deamidated proteins increased in the isoelectric region of untreated wheat gluten. The isoelectric point of succinic acid deamidated wheat gluten was shifted to a basic pH and existed in the broad pH regions. Foaming property and molecular flexibility of wheat gluten were improved after the modification. The hydrolysis degree of the hydrolysates in proteolysis with flavorzyme and pancreatin increased after succinic acid deamidation. Moreover, succinic acid deamidation-induced modification resulted in little change in molecular weight and secondary structure of the protein. Thus, succinic acid could facilitate unfolding protein conformation. In addition, it could improve protein-water interactions, surface properties, and sensibility of the proteolysis of the deamidated wheat gluten.

关键词： pH     isoelectric     conformation     deamidation-induced modification     molecular flexibility    

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Sorption of tetracycline to sediments and soils: assessing the roles of pH, the presence of cadmium and

Guixiang ZHANG, Xitao LIU, Ke SUN, Ye ZHAO, Chunye LIN

《环境科学与工程前沿（英文）》 2010年 第4卷 第4期   页码 421-429 doi: 10.1007/s11783-010-0265-3

摘要： Batch sorption experiments were conducted to evaluate the sorption behavior of tetracycline (TC, H L) on sediments and soils in the presence and absence of cadmium (Cd), as affected by pH and properties of sediments and soils. The results indicated stronger nonlinearity and higher capacity of TC sorption on sediments than on soils. Sorption of TC also strongly depended on environmental factors and sediment/soil properties. Lower pH facilitated TC sorption through a cation exchange mechanism, which also took place at pH values above 5.5, where TC existed as a zwitterion (H L ) or anions (HL and L ). When pH was above 7, however, ligand-promoted dissolution of TC might occur due to TC weakening the Al-O bond of aluminum oxide and the Fe-O bond of iron oxide. Natural organic matter (NOM) plays a more important role in TC sorption than cation exchange capacity (CEC) and clay contents. The presence of Cd (II) increased TC sorption on both sediments and soils, which resulted from the decrease of equilibrium solution pH caused by Cd exchange with H ions of sediment/soil surfaces. The increase of TC sorption was also related to the formation of TC-Cd complexes, where Cd acted as a bridge between the sediment/soil and TC.

关键词： sorption     tetracycline (TC)     pH     cadmium (Cd)     antibiotic    

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A Cu-modified active carbon fiber significantly promoted HS and PH simultaneous removal at a low reaction

《环境科学与工程前沿（英文）》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1425-3

摘要：

• Cu0.15-ACF performs the best for H2S and PH3 simultaneous removal.

关键词： ACF     H2S     PH3     Cu     Low temperature     Simultaneous removal    

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Decomposition of perfluorooctanoic acid by microwave-activated persulfate: Effects of temperature, pH

Yuchi LEE, Shanglien LO, Jeff KUO, Chinghong HSIEH

《环境科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 17-25 doi: 10.1007/s11783-011-0371-x

摘要： Microwave-hydrothermal treatment of persistent and bioaccumulative perfluorooctanoic acid (PFOA) in water with persulfate ( ) has been found effective. However, applications of this process to effectively remediate PFOA pollution require a better understanding on free-radical scavenging reactions that also take place. The objectives of this study were to investigate the effects of pH (pH= 2.5, 6.6, 8.8, and 10.5), chloride concentrations (0.01–0.15 mol·L ), and temperature (60°C, 90°C, and 130°C) on persulfate oxidation of PFOA under microwave irradiation. Maximum PFOA degradation occurred at pH 2.5, while little or no degradation at pH 10.5. Lowering system pH resulted in an increase in PFOA degradation rate. Both high pH and chloride concentrations would result in more scavenging of sulfate free radicals and slow down PFOA degradation. When chloride concentrations were less than 0.04 mol·L at 90°C and 0.06 mol·L at 60°C, presence of chloride ions had insignificant impacts on PFOA degradation. However, beyond these concentration levels, PFOA degradation rates reduced significantly with an increase in chloride concentrations, especially under the higher temperature.

关键词： microwave     perfluorooctanoic acid     pH     persulfate     chloride ions     perfluorocarboxylic acids    

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Tuning the electronic structure of NiCoP arrays through V doping for pH-universal hydrogen evolution

Yu Lin, Jinlei Wang, Duanlin Cao, Yaqiong Gong

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1134-1146 doi: 10.1007/s11705-020-2014-x

摘要： The exploration of cost-effective, high-performance, and stable electrocatalysts for the hydrogen evolution reaction (HER) over wide pH range (0–14) is of paramount importance for future renewable energy conversion technologies. Regulation of electronic structure through doping vanadium atoms is a feasible construction strategy to enhance catalytic activities, electron transfer capability, and stability of the HER electrode. Herein, V-doped NiCoP nanosheets on carbon fiber paper (CFP) (denoted as V -NiCoP/CFP) were constructed by doping V modulation on NiCoP nanosheets on CFP and used for pH-universal HER. Benefiting from the abundant catalytic sites and optimized hydrogen binding thermodynamics, the resultant V -NiCoP/CFP demonstrates a significantly improved HER catalytic activity, requiring overpotentials of 46.5, 52.4, and 85.3 mV to reach a current density of 10 mA·cm in 1 mol·L KOH, 0.5 mol·L H SO , and 1 mol·L phosphate buffer solution (PBS) electrolytes, respectively. This proposed cation-doping strategy provides a new inspiration to rationally enhance or design new-type nonprecious metal-based, highly efficient, and pH-universal electrocatalysts for various energy conversion systems.

关键词： hydrogen evolution reaction     transition metal phosphides     pH-universal     vanadium doping     carbon fiber paper    

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Acid resistance of methanogenic bacteria in a two-stage anaerobic process treating high concentration methanol wastewater

ZHOU Xuefei, REN Nanqi

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 53-56 doi: 10.1007/s11783-007-0010-8

摘要： In this study, the two-stage upflow anaerobic sludge blanket (UASB) system and batch experiments were employed to evaluate the performance of anaerobic digestion for the treatment of high concentration methanol wastewater. The acid resistance of granular sludge and methanogenic bacteria and their metabolizing activity were investigated. The results show that the pH of the first UASB changed from 4.9 to 5.8 and 5.5 to 6.2 for the second reactor. Apparently, these were not the advisable pH levels that common methanogenic bacteria could accept. The methanogenic bacteria of the system, viz. Methanosarcina barkeri, had some acid resistance and could still degrade methanol at pH 5.0. If the methanogenic bacteria were trained further, their acid resistance would be improved somewhat. Granular sludge of the system could protect the methanogenic bacteria within its body against the impact of the acidic environment and make them degrade methanol at pH 4.5. The performance of granular sludge was attributed to its structure, bacteria species, and the distribution of bacterium inside the granule.

关键词： pH     Granular     upflow anaerobic     advisable pH     methanogenic    

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标题 作者 时间 类型 操作

Effect of pH on biologic degradation of

Hongjing LI, Mengli HAO, Jingxian LIU, Chen CHEN, Zhengqiu FAN, Xiangrong WANG

期刊论文

Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production: effectof pH at ambient temperature

Leiyu FENG, Yuanyuan YAN, Yinguang CHEN

期刊论文

The effect of pH, solid content, water chemistry and ore mineralogy on the galvanic interactions between

Asghar Azizi, Seid Ziaoddin Shafaei, Mohammad Noaparast, Mohammad Karamoozian

期刊论文

4-Amino-1,8-naphthalimide based fluorescent photoinduced electron transfer (PET) pH sensors as liposomalcellular imaging agents: The effect of substituent patterns on PET directional quenching

Miguel Martínez-Calvo, Sandra A. Bright, Emma B. Veale, Adam F. Henwood, D. Clive Williams, Thorfinnur Gunnlaugsson

期刊论文

Effect of protein on PVDF ultrafiltration membrane fouling behavior under different pH conditions: interface

Xudong WANG,Miao ZHOU,Xiaorong MENG,Lei WANG,Danxi HUANG

期刊论文

Effect of environment change on the strength of cement/lime treated clays

Takenori HINO, Rui JIA, Seiji SUEYOSHI, Tri HARIANTO

期刊论文

Co-present Pb(II) accelerates the oxidation of organic contaminants by permanganate: Role of Pb(III)

期刊论文

Carbon dots-based fluorescence sensor for two-photon imaging of pH in diabetic mice

期刊论文

NO oxidation over Co-La catalysts and NO

Tiejun Zhang,Jian Li,Hong He,Qianqian Song,Quanming Liang

期刊论文

Effect of succinic acid deamidation-induced modification on wheat gluten

Lan LIAO, Mouming ZHAO, Haifeng ZHAO, Jiaoyan REN, Chun CUI, Xiao HU,

期刊论文

Sorption of tetracycline to sediments and soils: assessing the roles of pH, the presence of cadmium and

Guixiang ZHANG, Xitao LIU, Ke SUN, Ye ZHAO, Chunye LIN

期刊论文

A Cu-modified active carbon fiber significantly promoted HS and PH simultaneous removal at a low reaction

期刊论文

Decomposition of perfluorooctanoic acid by microwave-activated persulfate: Effects of temperature, pH

Yuchi LEE, Shanglien LO, Jeff KUO, Chinghong HSIEH

期刊论文

Tuning the electronic structure of NiCoP arrays through V doping for pH-universal hydrogen evolution

Yu Lin, Jinlei Wang, Duanlin Cao, Yaqiong Gong

期刊论文

Acid resistance of methanogenic bacteria in a two-stage anaerobic process treating high concentration methanol wastewater

ZHOU Xuefei, REN Nanqi

期刊论文