资源类型

期刊论文 460

会议视频 18

年份

2023 66

2022 46

2021 48

2020 40

2019 26

2018 21

2017 11

2016 24

2015 16

2014 14

2013 13

2012 15

2011 20

2010 15

2009 12

2008 22

2007 23

2006 11

2005 3

2004 4

展开 ︾

关键词

机理 9

双库协同机制 3

机制 3

2021全球工程前沿 2

DX桩 2

Maradbcm算法 2

作用机制 2

动力学 2

医学教育 2

原子力显微镜 2

工程前沿 2

木质素 2

环境 2

绿色化工 2

能源 2

2-基展开 1

2022全球工程前沿 1

21世纪海上丝绸之路 1

9 + 2结构 1

展开 ︾

检索范围:

排序: 展示方式:

Antioxidative potential of metformin: Possible protective mechanism against generating OH radicals

Huibin Guo, Ning Wang, Xiang Li

《环境科学与工程前沿(英文)》 2021年 第15卷 第2期 doi: 10.1007/s11783-020-1313-2

摘要: Abstract • Metformin consumes O2−• and OH• induced by PM are proposed. • OH• dominated the oxidation of metformin compared with O2−• • Metformin can prevent the harm of ROS induced by PM to human health. • Antioxidative potential of metformin was first proposed to provide measures. Exposure to particulate matter (PM) can lead to the excessive accumulation of reactive oxygen species (ROS), which causes oxidative stress and endangers human health. In this study, the effects of metformin on PM-induced radicals were investigated, and the antioxidation reaction mechanism of metformin was analyzed by the density functional theory (DFT) method. The corresponding results revealed that the consumption rate of dithiothreitol (DTT) increased as the metformin concentration (0–40 mmol/L) increased under exposure to PM active components. Moreover, the OH radical content decreased as the metformin concentration increased. This result may be related to the consumption of PM-induced OH radicals by metformin, which promotes the DTT consumption rate. Additionally, because the initiation reaction has a high barrier, the oxidation reaction rate between metformin and •O2− is not very fast, although various catalysts may be present in the human environment. Importantly, we found that the barrier of metformin induced by OH radicals is only 9.6 kcal/mol while the barrier of metformin induced by oxygen is 57.9 kcal/mol, which shows that the rate of the •OH-initiated oxidative reaction of metformin is much faster and that this reaction path occurs more easily. By sample analysis, the mean OH radical generation was 55 nmol/min/g (ranging from 5 to 105 nmol/min/g) on haze days and 30 nmol/min/g (ranging from 10 to 50 nmol/min/g) on non-haze days. Moreover, OH radical generation was higher on haze days than on neighboring non-haze days. Taken together, all data suggest that metformin could consume the PM-induced radicals, such as OH radicals and •O2−, thereby providing health protection.

关键词: Antioxidative potential     Metformin     Mechanism     OH radical     Health protection.    

Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1689-1699 doi: 10.1007/s11705-022-2186-7

摘要: Radicals are important intermediates in direct coal liquefaction. Certain radicals can cause the cleavage of chemical bonds. At high temperatures, radical fragments can be produced by the splitting of large organic molecules, which can break strong chemical bonds through the induction pyrolysis of radicals. The reaction between the formation and annihilation of coal radical fragments and the effect of hydrogen-donor solvents on the radical fragments are discussed in lignite hydrogenolysis. Using the hydroxyl and ether bonds as indicators, the effects of different radicals on the cleavage of chemical bond were investigated employing density functional theory calculations and lignite hydrogenolysis experiments. Results showed that the adjustment of the coal radical fragments could be made by the addition of hydrogen-donor solvents. Results showed that the transition from coal radical fragment to H radical leads to the variation of product distribution. The synergistic mechanism of hydrogen supply and hydrogenolysis of hydrogen-donor solvent was proposed.

关键词: direct coal liquefaction     hydrogen-donor solvent     induced pyrolysis     radical mechanism     density functional theory calculations    

Hydroxyl radical-involved cancer therapy via Fenton reactions

《化学科学与工程前沿(英文)》 2022年 第16卷 第3期   页码 345-363 doi: 10.1007/s11705-021-2077-3

摘要: The tumor microenvironment features over-expressed hydrogen peroxide (H2O2). Thus, versatile therapeutic strategies based on H2O2 as a reaction substrate to generate hydroxyl radical (•OH) have been used as a prospective therapeutic method to boost anticancer efficiency. However, the limited Fenton catalysts and insufficient endogenous H2O2 content in tumor sites greatly hinder •OH production, failing to achieve the desired therapeutic effect. Therefore, supplying Fenton catalysts and elevating H2O2 levels into cancer cells are effective strategies to improve •OH generation. These therapeutic strategies are systematically discussed in this review. Furthermore, the challenges and future developments of hydroxyl radical-involved cancer therapy are discussed to improve therapeutic efficacy.

关键词: hydroxyl radical     Fenton catalyst     hydrogen peroxide     cancer therapy    

structured -FeO/MoS effectively activated peroxymonosulfate for efficient abatement of bisphenol A via both radicaland non-radical pathways

《环境科学与工程前沿(英文)》 2023年 第18卷 第3期 doi: 10.1007/s11783-024-1797-2

摘要:

● Magnetic Co- γ -Fe2O3/MoS2 were prepared via facile hydrothermal methods.

关键词: Magnetic Co-γ-Fe2O3/MoS2     Hydrothermal method     Bisphenol A     Degradation pathways     Toxicity analysis    

Non-closure of the peritoneum and subcutaneous tissue at radical hysterectomy: A randomized controlled

Zhou-Fang XIONG MD, Wei-Hong DONG MD, Ze-Hua WANG MD,

《医学前沿(英文)》 2010年 第4卷 第1期   页码 112-116 doi: 10.1007/s11684-010-0016-7

摘要: We conducted a trial to assess the influence of closure or nonclosure of the peritoneum and subcutaneous tissue on the clinical outcomes of cervical cancer patients who underwent radical hysterectomy with lower abdominal cross incision. This randomized controlled trial was performed on 158 cervical cancer patients in our hospital between January 2002 and June 2004. Eighty-two patients were allocated to the “closure” group and 76 patients to the “nonclosure” group. Results showed that non-closure of the peritoneum and subcutaneous tissue could shorten operation time and febrile duration, reduce antibiotics requirement, increase the volume of drainage and decrease the incidence of liquefaction of subcutaneous fat (<0.05). There was no difference in blood loss, postoperative complications, bowel function restoration and post-operative stay between the two groups (>0.05). Our study revealed that closure of the peritoneum and subcutaneous tissue provides no immediate postoperative benefits while unnecessarily lengthening surgical time and anesthesia exposure. The practice of closure of the peritoneum and subcutaneous tissue at radical hysterectomy should be questioned.

关键词: cervical cancer     radical surgery     peritoneum     subcutaneous tissue    

Bacteria inactivation by sulfate radical: progress and non-negligible disinfection by-products

《环境科学与工程前沿(英文)》 2023年 第17卷 第3期 doi: 10.1007/s11783-023-1629-9

摘要:

● Status of inactivation of pathogenic microorganisms by SO4•− is reviewed.

关键词: Sulfate radicals     Disinfection by-products     Inactivation mechanisms     Bacterial inactivation     Water disinfection    

Free radical scavenging window of infertile patients with polycystic ovary syndrome: correlation with

null

《医学前沿(英文)》 2017年 第11卷 第2期   页码 247-252 doi: 10.1007/s11684-017-0519-6

摘要:

The activity of free radicals in follicular fluid was related to ovarian responsiveness, in vitro fertilization (IVF), and embryo transfer success rate. However, studies analyzing the relationship between the free radical scavenging capacity and embryo quality of infertile women with polycystic ovarian syndrome (PCOS) were lacking. The aim of this study was to evaluate the relationship between the free radical scavenging window of women with PCOS and their embryo quality. The free radical scavenging capacity of follicular fluid from women with PCOS was determined by a,a-diphenyl-b-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) assay, superoxide radical, and reactive oxygen species (ROS) assay. In the DPPH and ROS assays, the follicular fluid from grades I and II embryos was significantly higher than the follicular fluid from grades III and IV embryos. The lower control limit of DPPH radical scavenging capacity and upper control limit of ROS level were 13.2% and 109.0 cps, respectively. The calculated lower control limit and upper control limit were further confirmed in the follicular fluid of embryos of all grades. These cut-off values of free radical scavenging activity of follicular fluid could assist embryologists in choosing the development of embryos in PCOS patients undergoing IVF.

关键词: in vitro fertilization     PCOS     free radical     embryo quality    

Hydroxyl radical intensified Cu

Wenyue Li, Min Chen, Zhaoxiang Zhong, Ming Zhou, Weihong Xing

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1281-6

摘要: Abstract • Cu2O NPs/H2O2 Fenton process was intensified by membrane dispersion. • DMAc removal was enhanced to 98% for initial DMAc of 14000 mg/L. • Analyzed time-resolved degradation pathway of DMAc under ·OH attack. High-concentration industrial wastewater containing N,N-dimethylacetamide (DMAc) from polymeric membrane manufacturer was degraded in Cu2O NPs/H2O2 Fenton process. In the membrane-assisted Fenton process DMAc removal rate was up to 98% with 120 min which was increased by 23% over the batch reactor. It was found that ·OH quench time was extended by 20 min and the maximum ·OH productivity was notably 88.7% higher at 40 min. The degradation reaction rate constant was enhanced by 2.2 times with membrane dispersion (k = 0.0349 min−1). DMAc initial concentration (C0) and H2O2 flux (Jp) had major influence on mass transfer and kinetics, meanwhile, membrane pore size (rp) and length (Lm) also affected the reaction rate. The intensified radical yield, fast mass transfer and nanoparticles high activity all contributed to improve pollutant degradation efficiency. Time-resolved DMAc degradation pathway was analyzed as hydroxylation, demethylation and oxidation leading to the final products of CO2, H2O and NO3− (rather than NH3 from biodegradation). Continuous process was operated in the dual-membrane configuration with in situ reaction and separation. After five cycling tests, DMAc removal was all above 95% for the initial [DMAc]0 = 14,000 mg/L in wastewater and stability of the catalyst and the membrane maintained well.

关键词: Ceramic membrane reactor     N     N-dimethylacetamide     Fenton process     Cu2O     Wastewater treatment    

A pulsed switching peroxi-coagulation process to control hydroxyl radical production and to enhance 2,4

Yaobin Lu, Songli He, Dantong Wang, Siyuan Luo, Aiping Liu, Haiping Luo, Guangli Liu, Renduo Zhang

《环境科学与工程前沿(英文)》 2018年 第12卷 第5期 doi: 10.1007/s11783-018-1070-7

摘要:

• A new pulsed switching peroxi-coagulation (PSPC) system was developed.

• The ECT for 2,4-D removal in the PSPC was lower than that in the EF.

• The iron consumption for 2,4-D removal in the PSPC was lower than that in the PC.

关键词: Pulsed switching peroxi-coagulation system     Energy consumption     Hydroxyl radical production     2     4- Dichlorophenoxyacetic acid    

Zero-valent manganese nanoparticles coupled with different strong oxidants for thallium removal from wastewater

Keke Li, Huosheng Li, Tangfu Xiao, Gaosheng Zhang, Aiping Liang, Ping Zhang, Lianhua Lin, Zexin Chen, Xinyu Cao, Jianyou Long

《环境科学与工程前沿(英文)》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1213-5

摘要: • Nano zero-valent manganese (nZVMn, Mn0) is synthesized via borohydrides reduction. • Mn0 combined with persulfate/hypochlorite is effective for Tl removal at pH 6-12. • Mn0 can activate persulfate to form hydroxyl and sulfate radicals. • Oxidation-induced precipitation and surface complexation contribute to Tl removal. • Combined Mn0-oxidants process is promising in the environmental field. Nano zero-valent manganese (nZVMn, Mn0) was prepared through a borohydride reduction method and coupled with different oxidants (persulfate (S2O82−), hypochlorite (ClO−), or hydrogen peroxide (H2O2)) to remove thallium (Tl) from wastewater. The surface of Mn0 was readily oxidized to form a core-shell composite (MnOx@Mn0), which consists of Mn0 as the inner core and MnOx (MnO, Mn2O3, and Mn3O4) as the outer layer. When Mn0 was added alone, effective Tl(I) removal was achieved at high pH levels (>12). The Mn0-H2O2 system was only effective in Tl(I) removal at high pH (>12), while the Mn0-S2O82− or Mn0-ClO− system had excellent Tl(I) removal (>96%) over a broad pH range (4–12). The Mn0-S2O82− oxidation system provided the best resistance to interference from an external organic matrix. The isotherm of Tl(I) removal through the Mn0-S2O82− system followed the Freundlich model. The Mn0 nanomaterials can activate persulfate to produce sulfate radicals and hydroxyl radicals. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy suggested that oxidation-induced precipitation, surface adsorption, and electrostatic attraction are the main mechanisms for Tl(I) removal resulting from the combination of Mn0 and oxidants. Mn0 coupled with S2O82−/ClO− is a novel and effective technique for Tl(I) removal, and its application in other fields is worthy of further investigation.

关键词: Nano zero-valent manganese     Thallium     Adsorption     Oxidation     Sulfate radical     Hydroxyl radical    

Removal of nitric oxide from simulated flue gas using aqueous persulfate with activation of ferrous ethylenediaminetetraacetate in the rotating packed bed

《化学科学与工程前沿(英文)》 2023年 第17卷 第4期   页码 460-469 doi: 10.1007/s11705-022-2224-5

摘要: Nitric oxide being a major gas pollutant has attracted much attention and various technologies have been developed to reduce NO emission to preserve the environment. Advanced persulfate oxidation technology is a workable and effective choice for wet flue gas denitrification due to its high efficiency and green advantages. However, NO absorption rate is limited and affected by mass transfer limitation of NO and aqueous persulfate in traditional reactors. In this study, a rotating packed bed (RPB) was employed as a gas–liquid absorption device to elevate the NO removal efficiency (ηNO) by aqueous persulfate ((NH4)2S2O8) activated by ferrous ethylenediaminetetraacetate (Fe2+-EDTA). The experimental results regarding the NO absorption were obtained by investigating the effect of various operating parameters on the removal efficiency of NO in RPB. Increasing the concentration of (NH4)2S2O8 and liquid–gas ratio could promoted the oxidation and absorption of NO while the ηNO decreased with the increase of the gas flow and NO concentration. In addition, improving the high gravity factor increased the ηNO and the total volumetric mass transfer coefficient (KGα) which raise the ηNO up to more than 75% under the investigated system. These observations proved that the RPB can enhance the gas–liquid mass transfer process in NO absorption. The correlation formula between KGα and the influencing factors was determined by regression calculation, which is used to guide the industrial scale-up application of the system in NO removal. The presence of O2 also had a negative effect on the NO removal process and through electron spin resonance spectrometer detection and product analysis, it was revealed that Fe2+-EDTA activated (NH4)2S2O8 to produce •SO4, •OH and •O2, played a leading role in the oxidation of NO, to produce NO3 as the final product. The obtained results demonstrated a good applicable potential of RPB/PS/Fe2+-EDTA in the removal of NO from flue gases.

关键词: rotating packed bed     Fe2+-EDTA     sulfate radical     hydroxyl radical     NO removal efficiency    

Radical versus conservative surgical treatment of liver hydatid cysts: a meta-analysis

null

《医学前沿(英文)》 2018年 第12卷 第3期   页码 350-359 doi: 10.1007/s11684-017-0559-y

摘要:

To date, the efficacy of radical surgery (RS) versus conservative surgery (CS) for liver hydatid cysts (LHC) remains controversial. This meta-analysis was conducted to compare the two interventions. PubMed, Embase, and Web of Science were searched from their inceptions until June 2016. Meta-analysis was performed using STATA 12.0 software. We identified 19 eligible studies from 10 countries by retrieval. In total, 1853 LHC patients who received RS were compared with 2274 patients treated by CS. The risk of postoperative overall complication, biliary fistula, and recurrence was significantly lower, and operation time was significantly longer in the RS group. However, no statistically significant differences were found in terms of mortality risk and the duration of hospital stay between RS and CS. No significant publication biases were observed in all the above analyses. In conclusion, RS reduces the rates of postoperative complications and recurrence, whereas no trend toward such a reduction in mortality was observed in LHC patients.

关键词: liver hydatid cysts     radical surgery     conservative surgery     meta-analysis     complications    

Adjuvant chemotherapy versus adjuvant concurrent chemoradiotherapy after radical surgery for early-stage

《医学前沿(英文)》 2023年 第17卷 第1期   页码 93-104 doi: 10.1007/s11684-021-0892-z

摘要: We conducted a prospective study to assess the non-inferiority of adjuvant chemotherapy alone versus adjuvant concurrent chemoradiotherapy (CCRT) as an alternative strategy for patients with early-stage (FIGO 2009 stage IB–IIA) cervical cancer having risk factors after surgery. The condition was assessed in terms of prognosis, adverse effects, and quality of life. This randomized trial involved nine centers across China. Eligible patients were randomized to receive adjuvant chemotherapy or CCRT after surgery. The primary end-point was progression-free survival (PFS). From December 2012 to December 2014, 337 patients were subjected to randomization. Final analysis included 329 patients, including 165 in the adjuvant chemotherapy group and 164 in the adjuvant CCRT group. The median follow-up was 72.1 months. The three-year PFS rates were both 91.9%, and the five-year OS was 90.6% versus 90.0% in adjuvant chemotherapy and CCRT groups, respectively. No significant differences were observed in the PFS or OS between groups. The adjusted HR for PFS was 0.854 (95% confidence interval 0.415–1.757; P = 0.667) favoring adjuvant chemotherapy, excluding the predefined non-inferiority boundary of 1.9. The chemotherapy group showed a tendency toward good quality of life. In comparison with post-operative adjuvant CCRT, adjuvant chemotherapy treatment showed non-inferior efficacy in patients with early-stage cervical cancer having pathological risk factors. Adjuvant chemotherapy alone is a favorable alternative post-operative treatment.

关键词: chemotherapy     cervical cancer     lymph node metastasis     concurrent chemoradiotherapy     quality of life    

Light-induced variation in environmentally persistent free radicals and the generation of reactive radical

Yafang Shi, Yunchao Dai, Ziwen Liu, Xiaofeng Nie, Song Zhao, Chi Zhang, Hanzhong Jia

《环境科学与工程前沿(英文)》 2020年 第14卷 第6期 doi: 10.1007/s11783-020-1285-2

摘要: Abstract • Light irradiation increased the concentration of free radicals on HS. • The increased spin densities on HS readily returned back to the original value. • The “unstable” free radicals induced the formation of reactive radical species. • Reactive radicals’ concentration correlated strongly with EPFRs’ concentration. Environmentally persistent free radicals (EPFRs) in humic substances play an essential role in soil geochemical processes. Light is known to induce EPFRs formation for dissolved organic matter in aquatic environments; however, the impacts of light irradiation on the variation of EPFRs in soil humic substances remain unclear. In this study, humic acid, fulvic acid, and humin were extracted from peat soil and then in situ irradiated using simulated sunlight. Electron paramagnetic resonance spectroscopy results showed that with the increasing irradiation time, the spin densities and g-factors of humic substances rapidly increased during the initial 20 min and then gradually reached a plateau. After irradiation for 2h, the maximum spin density levels were up to 1.63 × 1017, 2.06 × 1017, and 1.77 × 1017 spins/g for the humic acid, fulvic acid, and humin, respectively. And the superoxide radicals increased to 1.05 × 1014–1.46 × 1014 spins/g while the alkyl radicals increased to 0.47 × 1014–1.76 × 1014 spins/g. The light-induced EPFRs were relatively unstable and readily returned back to their original state under dark and oxic conditions. Significant positive correlations were observed between the concentrations of EPFRs and reactive radical species (R2 = 0.65–0.98, p<0.05), which suggested that the newly produced EPFRs contributed to the formation of reactive radical species. Our findings indicate that under the irradiation humic substances are likely to be more toxic and reactive in soil due to the formation of EPFRs.

关键词: Peat     Humic substances     Environmentally persistent free radicals     Light irradiation     Reactive radical species    

Insights into the electron transfer mechanisms of permanganate activation by carbon nanotube membrane for enhanced micropollutants degradation

《环境科学与工程前沿(英文)》 2023年 第17卷 第9期 doi: 10.1007/s11783-023-1706-0

摘要:

● A CNT filter enabled effective KMnO4 activation via facilitated electron transfer.

关键词: KMnO4     Carbon nanotubes     Non-radical pathway     Electron transfer     Water treatment    

标题 作者 时间 类型 操作

Antioxidative potential of metformin: Possible protective mechanism against generating OH radicals

Huibin Guo, Ning Wang, Xiang Li

期刊论文

Regulation of radicals by hydrogen-donor solvent in direct coal liquefaction

期刊论文

Hydroxyl radical-involved cancer therapy via Fenton reactions

期刊论文

structured -FeO/MoS effectively activated peroxymonosulfate for efficient abatement of bisphenol A via both radicaland non-radical pathways

期刊论文

Non-closure of the peritoneum and subcutaneous tissue at radical hysterectomy: A randomized controlled

Zhou-Fang XIONG MD, Wei-Hong DONG MD, Ze-Hua WANG MD,

期刊论文

Bacteria inactivation by sulfate radical: progress and non-negligible disinfection by-products

期刊论文

Free radical scavenging window of infertile patients with polycystic ovary syndrome: correlation with

null

期刊论文

Hydroxyl radical intensified Cu

Wenyue Li, Min Chen, Zhaoxiang Zhong, Ming Zhou, Weihong Xing

期刊论文

A pulsed switching peroxi-coagulation process to control hydroxyl radical production and to enhance 2,4

Yaobin Lu, Songli He, Dantong Wang, Siyuan Luo, Aiping Liu, Haiping Luo, Guangli Liu, Renduo Zhang

期刊论文

Zero-valent manganese nanoparticles coupled with different strong oxidants for thallium removal from wastewater

Keke Li, Huosheng Li, Tangfu Xiao, Gaosheng Zhang, Aiping Liang, Ping Zhang, Lianhua Lin, Zexin Chen, Xinyu Cao, Jianyou Long

期刊论文

Removal of nitric oxide from simulated flue gas using aqueous persulfate with activation of ferrous ethylenediaminetetraacetate in the rotating packed bed

期刊论文

Radical versus conservative surgical treatment of liver hydatid cysts: a meta-analysis

null

期刊论文

Adjuvant chemotherapy versus adjuvant concurrent chemoradiotherapy after radical surgery for early-stage

期刊论文

Light-induced variation in environmentally persistent free radicals and the generation of reactive radical

Yafang Shi, Yunchao Dai, Ziwen Liu, Xiaofeng Nie, Song Zhao, Chi Zhang, Hanzhong Jia

期刊论文

Insights into the electron transfer mechanisms of permanganate activation by carbon nanotube membrane for enhanced micropollutants degradation

期刊论文