资源类型

期刊论文 35

年份

2023 1

2022 2

2021 3

2020 2

2017 4

2016 3

2015 3

2013 1

2012 3

2011 3

2010 4

2009 2

2008 1

2007 1

2005 1

2003 1

展开 ︾

关键词

pH值 2

H2S 1

P4 1

PH3 1

云无线接入网；智能反射面；传输波束成形；前传压缩 1

催化剂 1

催化氧化 1

可降解塑料 1

固定床 1

地下水 1

水解反应 1

碳酸平衡 1

碳酸盐岩 1

裂纹扩展 1

展开 ︾

检索范围：

排序： 展示方式：

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    

HTML PDF 收藏

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    

HTML PDF 收藏

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    

HTML PDF 收藏

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    

HTML PDF 收藏

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    

HTML PDF 收藏

Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production: effect of pH

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    

HTML PDF 收藏

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    

HTML PDF 收藏

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    

HTML PDF 收藏

Aptamer-coded DNA nanoparticles for targeted doxorubicin delivery using pH-sensitive spacer

Pengwei Zhang, Junxiao Ye, Ergang Liu, Lu Sun, Jiacheng Zhang, Seung Jin Lee, Junbo Gong, Huining He, Victor C. Yang

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 529-536 doi: 10.1007/s11705-017-1645-z

摘要： An anticancer drug delivery system consisting of DNA nanoparticles synthesized by rolling circle amplification (RCA) was developed for prostate cancer membrane antigen (PSMA) targeted cancer therapy. The template of RCA was a DNA oligodeoxynucleotide coded with PSMA-targeted aptamer, drug-loading domain, primer binding site and pH-sensitive spacer. Anticancer drug doxorubicin, as the model drug, was loaded into the drug-loading domain (multiple GC-pair sequences) of the DNA nanoparticles by intercalation. Due to the integrated pH-sensitive spacers in the nanoparticles, in an acidic environment, the cumulative release of doxorubicin was far more than the cumulative release of the drug in the normal physiological environment. In cell uptake experiments, treated with doxorubicin loaded DNA nanoparticles, PSMA-positive C4-2 cells could take up more doxorubicin than PSMA-null PC-3 cells. The prepared DNA nanoparticles showed the potential as drug delivery system for PSMA targeting prostate cancer therapy.

关键词： aptamer     DNA nanoparticles     rolling circle amplification     doxorubicin     drug delivery     pH sensitive    

HTML PDF 收藏

Efficient dechlorination of 2,4-dichlorophenol in an aqueous media with a mild pH using a Pd/TiO

Jiangkun DU,Jianguo BAO,Wei HU

《环境科学与工程前沿（英文）》 2015年 第9卷 第5期   页码 919-928 doi: 10.1007/s11783-015-0794-x

摘要： In this study, palladium-loaded titania nanotubes was fabricated on a titanium plate (Pd/TiO NTs/Ti) for efficient electrodechlorination of 2,4-chlorophenol with a mild pH condition. The nature of Pd/TiO NTs/Ti electrodes was characterized by field-emission scanning electron microscope (FESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and cyclic voltammetry (CV) techniques. The characterization results indicated the generation of Pd nanoparticles which were evenly dispersed on titania nanotubes arrays on the Pd/TiO NTs/Ti surface. An effective degradation efficiency of up to 91% was achieved within 60 min at cathode potential of −0.7 V ( SCE) and initial pH of 5.5. The effects of the applied cathode potential and initial pH on the degradation efficiency were studied. A near neutral condition was more favorable since very low and very high pHs were not conducive to the dechlorination process. Furthermore, the intermediates analysis showed that the Pd/TiO NTs/Ti electrode could completely remove chlorine from 2, 4-dichlorophenol since only phenol was detected as the byproduct and the concentration of released chlorine ions indicated near-complete dechlorination. This work presents a good alternative technique for eliminating persistent chlorophenols in polluted wastewater without maintaining strong acidic environment.

关键词： Pd/TiO2NTs/Ti cathode     chlorophenols     electrocatalytic dechlorination     wastewater treatment    

HTML PDF 收藏

Removing ammonia from air with a constant pH, slightly acidic water　spray wet scrubber using recycled

Ahmad Kalbasi Ashtari, Amir M. Samani Majd, Gerald L. Riskowski, Saqib Mukhtar, Lingying Zhao

《环境科学与工程前沿（英文）》 2016年 第10卷 第6期 doi: 10.1007/s11783-016-0869-3

摘要： Slightly acidic solutions are a practical means of removing ammonia from air Scrubbed NH accumulates in solution as NH and should be an excellent fertilizer Increased air velocity decreased NH removal and increased NH collection Previous research on wet scrubbers has only studied highly acidic scrubbing solutions because of their high ammonia capture efficiencies; however, the high acidity created practical problems. Lower acidity solutions would reduce corrosion, maintenance, and cost; however, designers may need to use strategies for increasing scrubber effectiveness, such as using lower air velocities. The objective of this study was to determine if a spray scrubber with slightly acidic and higher pH scrubbing solution (pH from 2 to 8) could effectively remove NH from NH laden air (such as animal building exhaust air), and also collect this valuable resource for later use as a fertilizer. A bench-scale spray wet scrubber treated 20 ppmv NH /air mixture in a countercurrent contact chamber. First, the solution pH was varied from 2 to 8 while maintaining constant air velocity at 1.3 m·s . Next, air velocity was increased (2 and 3 m·s ) while solution pH remained constant at pH6. At 1.3 m·s , NH removal efficiencies ranged between 49.0% (pH8) and 84.3% (pH2). This study has shown that slightly acidic scrubbing solutions are a practical means of removing ammonia from air especially if the scrubber is designed to increase collisions between solution droplets and NH molecules. The NH removed from the air was held in solution as NH and accumulates over time so the solution should be an excellent fertilizer.

关键词： Ammonia     Spray wet scrubber     Slightly acidic scrubbing solution     Controlled pH     Removal efficiency    

HTML PDF 收藏

容易断裂的可降解塑料 Letter

杨栩旭, Jason Steck, 杨加伟, 王叶成, 锁志刚

《工程（英文）》 2021年 第7卷 第5期   页码 624-629 doi: 10.1016/j.eng.2021.02.009

摘要： 最终发现在加载的能量释放率范围内，裂纹扩展速率对载荷的变化不敏感，却对湿度和pH值具有较高的敏感性。这些发现将有助于可降解塑料的发展，并在医疗行业和环境可持续性发展方面具有重要意义。

关键词： 可降解塑料     水解反应     pH值     裂纹扩展    

HTML PDF 收藏

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    

HTML PDF 收藏

地下水碳酸平衡检查系统

刘建刚,郑克勋,傅伟宁,吴顺华

《中国工程科学》 2003年 第5卷 第9期   页码 61-64

摘要：

文章主要研究地下水在不同温度和CO2分压条件下碳酸三种存在形式与pH值的关系，以便更有效地对地下水水质资料进行可靠性检查。分析认为HCO3-出现峰值的分界pH0值，纯水在CO2分压1～105Pa，温度0～30℃时的变化范围为pH0值随温度的升高而降低。石灰岩和白云岩的pH0十分接近，碳酸盐岩地区的平衡特性将取决于方解石成分。

关键词： 碳酸盐岩     地下水     碳酸平衡     pH值    

HTML PDF 收藏

Arsenic (V) removal from groundwater by GE-HL nanofiltration membrane: effects of arsenic concentration, pH

Xiaowei WANG, Wenjun LIU, Weifang MA, Desheng LI,

《环境科学与工程前沿（英文）》 2009年 第3卷 第4期   页码 428-433 doi: 10.1007/s11783-009-0146-9

摘要： A laboratory-scale investigation was performed to study arsenic (As (V)) removal by negatively charged GE-HL nanofiltration (NF) membrane in simulated drinking water. Effects of As (V) concentration (0–200μg·L), pH, and co-ions and counter-ions were investigated. The NF membrane presented good stability, and the rejection rates exceeded 90%. The rejection rates of As (V) decreased with the increase of As (V) concentration, while it increased with the increase of pH (reached 96% at pH 6.75). Moreover, a negative relationship was observed between the co-existing ions of Cl, Na, SO, and Ca and the removal of As (V), in which bivalent ions presented more significant effects than monovalent ions.

关键词： nanofiltration (NF)     rejection rate     co-existing ion     co-ion     counter-ion    

HTML PDF 收藏

标题 作者 时间 类型 操作

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

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

Effect of pH on biologic degradation of

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

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

Co-fermentation of waste activated sludge with food waste for short-chain fatty acids production: effect of pH

Leiyu FENG, Yuanyuan YAN, Yinguang CHEN

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

Aptamer-coded DNA nanoparticles for targeted doxorubicin delivery using pH-sensitive spacer

Pengwei Zhang, Junxiao Ye, Ergang Liu, Lu Sun, Jiacheng Zhang, Seung Jin Lee, Junbo Gong, Huining He, Victor C. Yang

期刊论文

Efficient dechlorination of 2,4-dichlorophenol in an aqueous media with a mild pH using a Pd/TiO

Jiangkun DU,Jianguo BAO,Wei HU

期刊论文

Removing ammonia from air with a constant pH, slightly acidic water　spray wet scrubber using recycled

Ahmad Kalbasi Ashtari, Amir M. Samani Majd, Gerald L. Riskowski, Saqib Mukhtar, Lingying Zhao

期刊论文

容易断裂的可降解塑料

杨栩旭, Jason Steck, 杨加伟, 王叶成, 锁志刚

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

地下水碳酸平衡检查系统

刘建刚,郑克勋,傅伟宁,吴顺华

期刊论文

Arsenic (V) removal from groundwater by GE-HL nanofiltration membrane: effects of arsenic concentration, pH

Xiaowei WANG, Wenjun LIU, Weifang MA, Desheng LI,

期刊论文