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Mutual detoxification of mercury and selenium in unicellular Tetrahymena

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Journal of Environmental Sciences 2018年第6期30卷 143-150页

作者： Cheng-bin Liu Li Zhang Qi Wu Guang-bo Qu Yong-guang Yin Li-gang Hu Jian-bo Shi gui-bin jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences College of Resources and Environment University of Chinese Academy of Sciences Institute of Environment and Health Jianghan University

Selenium（Se） is commonly recognized as a protective element with an antagonistic effect against mercury（Hg） toxicity. However, the mechanisms of this Hg–Se antagonism are complex and remain controversial. To gain insight into the Hg–Se antagonism, a type of unicellular eukaryotic protozoa（Tetrahymena malaccensis, T. malaccensis） was selected and individually or jointly exposed to two Hg and three Se species. We found that Se species showed different toxic effects on the proliferation of T. malaccensis with the toxicity following the order：selenite（Se（IV））〉 selenomethionine（SeMeth）〉 selenate（Se（VI））. The Hg–Se antagonism in Tetrahymena was observed because the joint toxicity significantly decreased under co-exposure to highly toxic dosages of Hg and Se versus individual toxicity. Unlike Se（IV） and Se（VI）, non-toxic dosage of SeM eth significantly decreased the Hg toxicity, revealing the influence of the Se species and dosages on the Hg–Se antagonism. Unexpectedly, inorganic divalent Hg（Hg2＋） and monomethylmercury（MeHg） also displayed detoxification towards extremely highly toxic dosages of Se, although their detoxifying efficiency was discrepant. These results suggested mutual Hg–Se detoxification in T. malaccensis, which was highly dependent on the dosages and species of both elements. As compared to other species, SeM eth and MeHg promoted the Hg–Se joint effects to a higher degree. Additionally, the Hg contents decreased for all the Hg–Se co-exposed groups, revealing a sequestering effect of Se towards Hg in T. malaccensis.

关键词： Mercury Selenium Antagonism Mutual detoxification Species

Synthesis of Poly(aryl ether ketone) Copolymers Containing Adamantyl-substituted Naphthalene Rings

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Chemical Research in Chinese Universities 2009年第2期25卷 261-264页

作者： ZHU Xiao-liang ZHANG Shu-ling REN Dian-fu GUAN Shao-wei WANG gui-bin jiang Zhen-hua College of Chemistry Jilin University Changchun 130012 P R. China

High performance polymers have received considerable attention over the past decade owing to their increased demands as replacements for metals or ceramics in automotive, aerospace, and microelectronic industries. Poly（aryl ether ketone）s（PAEKs） are a class of important high-performance aromatic polymers with excellent mechanical properties, good solvent resistance, size-accuracy, electrical characteristics, and superior thermal stability. However,

关键词： Adamantyl group Naphthalene Poly(aryl ether ketone) Synthesis

Simultaneous determination of Dow and pKa with hollow fiber-protected negligible depletion liquid-phase microextraction

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Simultaneous determination of Dow and pKa with hollow fiber-...

Metal nanoparticles decorated CoFe-(oxy)hydroxysulfides nanosheets fabricated by a general strategy for electrocatalytic water splitting

第十二届北京分析测试学术报告会暨展览会(BCEIA 2007)

作者： Xiao-qiang Cai Jing-fu Liu Xia-lin Hu Zi-fu Li gui-bin jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Civil and Environment Engineering School University of Science and TechnologyBeijing

Distribution coefficient(D) and acid dissociation constant(pK) are key parameters of a polar compound, and many methods have been developed for their determination. However, most of these methods can only measure D and pK, respectively. Therefore, it is of interest to develop methods that can determine D and pK a simultaneously. In this study, by using phenol, 4-chlorophenol(4-CP) and 2,4-dichlorophenol(2,4-DCP) as model compounds, a new method based on hollow fiber-protected negligible depletion liquid-phase microextraction(HF-nd-LPME) coupled with high performance liquid chromatography(HPLC) was developed for the simultaneous determination of D and pK a. The HF-nd-LPME device was prepared as follows: polypropylene hollow fiber membranes(HF, 200 μm wall thickness, 600 μm inner diameter) manually cut into 37 mm-length were ultrasonic cleaning for 10 min with acetone. Then, the HF was taken out and exposed to the air till the acetone in HF was completely volatilized, and both ends of the HF were sealed with a heated stainless iron tweezers. After that, the two-end-sealed HF was immerged in 1-octanol and sonicated for 6 h in order to impregnate the lumen of HF with 1-octanol. Finally, the hollow fiber was taken out and immersed into water and then shaken about 1 min to wash out surplus organic solvent. For extraction, the above-prepared The HF-nd-LPME device was deployed in 500 ml of sample solution(2 μg/m L phenol, 4-CP and 2,4-DCP) prepared in 1-octanol saturated 1 m M NaHPO buffer and stirred(1200 r/min) for 5 h to ensure distribution equilibration of the target compounds between the 1-octanol and aqueous phases. Then, the HF-nd-LPME device was harvested and subsequently the two sealed ends were cut open to flush the 1-octanol into a 200-μL glass vial with a 5 mL syringe. Then, 10 μL. Usually, 8 μL of 1-octanol can be harvested, of which 5 μLwas manually aspirated into a HPLC microsyringe and injected into the HPLC system for the determination of compound concentra

关键词： Dow pKa Hollow fiber LPME Simultaneous determination

来源： cnki会议评论

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Journal of Energy Chemistry 2025年第1期100卷 26-38页

作者： Xiaodong Yang Haochen Shen Xiaoming Xiao Zhichao Li Qi Zhou Wei Yang bin jiang Yongli Sun Luhong Zhang Zhenhua Yan School of Chemical Engineering and Technology Tianjin University Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education) Nankai University

This study presents a novel method to fabricate metal-decorated,sulfur-doped layered double hydroxides （M/SLDH） through spontaneous redox and sulfurization *** developed Ag/SLDH and Pt/SLDH catalysts with abundant heterogeneous interfaces and hierarchical nanostructures demonstrated outstanding oxygen evolution reaction （OER） and hydrogen evolution reaction （HER） performance,achieving low overpotentials of 212 and 35 mV at 10 mA cm-2in 1 M KOH,*** both anode and cathode in water splitting,they required only 1.47 V to reach 10 mA cm-2and exhibited high structural robustness,maintaining stability at 1000 mA cm-2for 300 ***-situ Raman analysis revealed that the synergistic effects of metal nanoparticles and S doping significantly promote the transformation into the S-Co1-xFexOOH layer,which serves as the active phase for water ***,ultraviolet photoelectron spectroscopy （UPS） and density functional theory （DFT） analyses indicated that incorporating metal nanoparticles and S doping increase electron density near the Fermi level and reduce reaction energy barriers,thus enhancing intrinsic OER and HER *** study provides a scalable strategy for synthesizing high-performance electrocatalysts for water splitting,with promising potential for broader applications.

关键词： LDH Spontaneous reaction Metal nanoparticles Water splitting

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

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Neural Regeneration Research 2025年第6期20卷 1764-1775页

作者： Zhenzhong Zheng Jialin Chen Jinghong Xu bin jiang Lei Li Yawei Li Yuliang Dai bing Wang Department of Spine Surgery The Second Xiangya Hospital of Central South UniversityChangshaHunan ProvinceChina

Degenerative cervical myelopathy is a common cause of spinal cord injury,with longer symptom duration and higher myelopathy severity indicating a worse *** numerous studies have investigated serological biomarkers for acute spinal cord injury,few studies have explored such biomarkers for diagnosing degenerative cervical *** study involved 30 patients with degenerative cervical myelopathy(51.3±7.3 years old,12 women and 18 men),seven healthy controls(25.7±1.7 years old,one woman and six men),and nine patients with cervical spondylotic radiculopathy(51.9±8.6 years old,three women and six men).Analysis of blood samples from the three groups showed clear differences in transcriptomic *** analysis identified 128 differentially expressed genes that were enriched in patients with neurological *** least absolute shrinkage and selection operator analysis,we constructed a five-gene model(TBCD,TPM2,PNKD,EIF4G2,and AP5Z1)to diagnose degenerative cervical myelopathy with an accuracy of 93.5%.One-gene models(TCAP and SDHA)identified mild and severe degenerative cervical myelopathy with accuracies of 83.3%and 76.7%,*** of two immune cell types(memory B cells and memory-activated CD4^(+)T cells)predicted levels of lesions in degenerative cervical myelopathy with 80%*** results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

关键词： biomarkers candidate genes degenerative cervical myelopathy gene expression analysis immune cell types neurological disabilities peripheral blood RNA profiles spinal cord injury

Impacts of the annual cycle of background SST in the tropical Pacific on the phase and amplitude of ENSO

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 12-17页

作者： Song jiang Congwen Zhu Ning jiang State Key Laboratory of Severe Weather(LASW) Chinese Academy of Meteorological SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina

The dominant annual cycle of sea surface temperature(SST)in the tropical Pacific exhibits an antisymmetric mode,which explains 83.4%total variance,and serves as a background of El Niño-Southern Oscillation(ENSO).However,there is no consensus yet on its anomalous impacts on the phase and amplitude of *** on data during 1982-2022,results show that anomalies of the antisymmetric mode can affect the evolution of ENSO on the interannual scale via Bjerknes feedback,in which the positive(negative)phase of the antisymmetric mode can strengthen El Niño(La Niña)in boreal winter via an earlier(delayed)seasonal cycle transition and larger(smaller)annual *** magnitude of the SST anomalies in the equatorial eastern Pacific can reach more than±0.3◦C,regulated by the changes in the antisymmetric mode based on random sensitivity *** reveal the spatial pattern of the annual cycle associated with the seasonal phase-locking of ENSO evolution and provide new insight into the impact of the annual cycle of background SST on ENSO,which possibly carries important implications for forecasting ENSO.

关键词： Annual cycle SST anomaly Antisymmetric mode ENSO

Direct hydride derivatization of methyl- and ethylmercury chlorides in aqueous solution with KBH_4

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Journal of Environmental Sciences 2000年第3期12卷 275-278页

作者： HE bin jiang gui-bin Research Centre for Eco Environmental Sciences Chinese Academy of SciencesBeijing 10085China

A convenient hydride derivatization procedure of methyl\|and ethylmercury chlorides to volatile hydrides was reported. In sealed vials methylmercury and ethylmercury compounds in acidic aqueous solutions were converted into their volatile forms by the reaction with potassium tetrahydroborate(KBH 4) and elvolved to the headspace of the vials. The gaseous analytes in the headspace were extracted and concentrated by solid phase microextraction(SPME) and injected into gas chromatography (GC) for separation and identified by mass selective detector(MS).

关键词： hydride derivatization methyl\| and ethylmercury gas chromatography mass selective detector

基于2018-2022年国家自然科学基金结题项目分析干细胞研究现状

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中国组织工程研究 2025年第19期29卷 4145-4150页

作者：蒋君张玢中国医学科学院医学信息研究所北京市100005

背景:目前大多数研究从国家自然科学基金资助论文和项目申请角度出发,对干细胞某一方面进行深入分析,或者验证某种评价方法,缺乏对干细胞领域国家自然科学基金已结题项目的全面分析。目的:了解2018-2022年干细胞领域国家自然科学基金结... 详细信息

背景:目前大多数研究从国家自然科学基金资助论文和项目申请角度出发,对干细胞某一方面进行深入分析,或者验证某种评价方法,缺乏对干细胞领域国家自然科学基金已结题项目的全面分析。目的:了解2018-2022年干细胞领域国家自然科学基金结题项目资助情况及研究热点,为后续研究提供参考。

关键词：干细胞国家自然科学基金聚类分析研究热点文献计量学

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He Li Li Sai Wang Shao-jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max Planck Institute for Gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(GWs) within the standard model of particle physics. If these background GWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes