Removal of chlorinated organic solvents from hydraulic fracturing wastewater by bare and entrapped nanoscale zero-valent iron

Lei, Cheng,Sun, Yuqing,Khan, Eakalak,Chen, Season S.,Tsang, Daniel C.W.,Graham, Nigel J.D.,Ok, Yong Sik,Yang, Xin,Lin, Daohui,Feng, Yujie,Li, Xiang-Dong Elsevier 2018 CHEMOSPHERE - Vol.196 No.-

<P><B>Abstract</B></P> <P>With the increasing application of hydraulic fracturing, it is urgent to develop an effective and economically feasible method to treat the large volumes of fracturing wastewater. In this study, bare and entrapped nanoscale zero-valent iron (nZVI) were introduced for the removal of carbon tetrachloride (CT) and 1,1,2-trichloroethane (TCA) in model high-salinity fracturing wastewater. With increasing ionic strength (<I>I</I>) from Day-1 (<I>I</I> = 0.35 M) to Day-90 (<I>I</I> = 4.10 M) wastewaters, bare nZVI presented significantly lower removal efficiency of CT (from 53.5% to 38.7%) and 1,1,2-TCA (from 71.1% to 21.7%) and underwent more serious Fe dissolution from 1.31 ± 1.19% in Day-1 to 5.79 ± 0.32% in Day-90 wastewater. Particle aggregation induced by high ionic strength was primarily responsible for the lowered performance of nZVI due to less available reactive sites on nZVI surface. The immobilization of nZVI in alginate with/without polyvinyl alcohol provided resistance to particle aggregation and contributed to the superior performance of entrapped nZVI in Day-90 wastewater for 1,1,2-TCA removal (62.6–72.3%), which also mitigated Fe dissolution (4.00–4.69%). Both adsorption (by polymer matrix) and reduction (by immobilized nZVI) were involved in the 1,1,2-TCA removal by entrapped nZVI. However, after 1-month immersion in synthetic fracturing wastewater, a marked drop in the reactivity of entrapped nZVI for 1,1,2-TCA removal from Day-90 wastewater was observed with significant release of Na and total organic carbon. In summary, bare nZVI was sensitive to the nature of the fracturing wastewater, while the use of environmentally benign entrapped nZVI was more promising for wastewater treatment.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Increasing ionic strength decreased nZVI reactivity and increased Fe dissolution. </LI> <LI> Entrapping nZVI in polymer matrix improved reactivity and limited Fe dissolution. </LI> <LI> Entrapped nZVI removed model chlorinated organic via both adsorption and reduction. </LI> <LI> Aging process was mitigated by polymer matrix but still inhibited nZVI reactivity. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Nanoscale zero-valent iron for metal/metalloid removal from model hydraulic fracturing wastewater

Sun, Yuqing,Lei, Cheng,Khan, Eakalak,Chen, Season S.,Tsang, Daniel C.W.,Ok, Yong Sik,Lin, Daohui,Feng, Yujie,Li, Xiang-dong Elsevier 2017 CHEMOSPHERE - Vol.176 No.-

<P><B>Abstract</B></P> <P>Nanoscale zero-valent iron (nZVI) was tested for the removal of Cu(II), Zn(II), Cr(VI), and As(V) in model saline wastewaters from hydraulic fracturing. Increasing ionic strength (<I>I</I>) from 0.35 to 4.10 M (Day-1 to Day-90 wastewaters) increased Cu(II) removal (25.4–80.0%), inhibited Zn(II) removal (58.7–42.9%), slightly increased and then reduced Cr(VI) removal (65.7–44.1%), and almost unaffected As(V) removal (66.7–75.1%) by 8-h reaction with nZVI at 1–2 g L<SUP>−1</SUP>. The removal kinetics conformed to pseudo-second-order model, and increasing <I>I</I> decreased the surface area-normalized rate coefficient (<I>k</I> <SUB> <I>sa</I> </SUB>) of Cu(II) and Cr(VI), probably because agglomeration of nZVI in saline wastewaters restricted diffusion of metal(loid)s to active surface sites. Increasing <I>I</I> induced severe Fe dissolution from 0.37 to 0.77% in DIW to 4.87–13.0% in Day-90 wastewater; and Fe dissolution showed a significant positive correlation with Cu(II) removal. With surface stabilization by alginate and polyvinyl alcohol, the performance of entrapped nZVI in Day-90 wastewater was improved for Zn(II) and Cr(VI), and Fe dissolution was restrained (3.20–7.36%). The X-ray spectroscopic analysis and chemical speciation modelling demonstrated that the difference in removal trends from Day-1 to Day-90 wastewaters was attributed to: (i) distinctive removal mechanisms of Cu(II) and Cr(VI) (adsorption, (co-)precipitation, and reduction), compared to Zn(II) (adsorption) and As(V) (bidentate inner-sphere complexation); and (ii) changes in solution speciation (e.g., from Zn<SUP>2+</SUP> to ZnCl<SUB>3</SUB> <SUP>−</SUP> and ZnCl<SUB>4</SUB> <SUP>2−</SUP>; from CrO<SUB>4</SUB> <SUP>2−</SUP> to CaCrO<SUB>4</SUB> complex). Bare nZVI was susceptible to variations in wastewater chemistry while entrapped nZVI was more stable and environmentally benign, which could be used to remove metals/metalloids before subsequent treatment for reuse/disposal.</P> <P><B>Highlights</B></P> <P> <UL> <LI> nZVI could remove Cu(II), Zn(II), Cr(VI), and As(V) from fracturing wastewaters. </LI> <LI> High salinity enhanced Fe dissolution and reduced removal rates except Cu(II). </LI> <LI> nZVI entrapment mitigated Fe dissolution and improved metal(loid) removal. </LI> <LI> Removal efficiency varied with interaction mechanisms and solution speciation. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Organo-layered double hydroxides for the removal of polycyclic aromatic hydrocarbons from soil washing effluents containing high concentrations of surfactants

Zhang, Ming,Zhao, Cheng,Li, Jinye,Xu, Liheng,Wei, Fang,Hou, Deyi,Sarkar, Binoy,Ok, Yong Sik Elsevier 2019 Journal of hazardous materials Vol.373 No.-

<P><B>Abstract</B></P> <P>Disposal of soil washing effluent (SWE) resulting from the surfactant-enhanced remediation of soil containing hydrophobic organic contaminants (HOCs)is complicated because of the presence of high levels of surfactants. The synthesized layered double hydroxides (LDHs), modified with sodium dodecyl sulfonate (SDS) in different loading amounts (organo-LDHs),were evaluated in this study as sorbents for the removal of two typical HOCs, phenanthrene (PHE) and pyrene (PYR),from a simulative SWE. The results showed that the organo-LDHs can effectively sorb PHE and PYR from the SWE within an equilibrium time of 2 h. All isotherms were linear and the sorption capabilities of the organo-LDHs increased almost linearly with the increase in the amount of SDS loaded on the LDHs. Besides, the surface areas of the organo-LDHs decreased sharply with the increase in SDS loading owing to the hindrance of the exposed surface of the LDHs by the incorporated SDS. These findings indicated that partitioning dominated the sorption process rather than adsorption, and the strong affinity of HOCs towards the organic phase in LDHs assisted in the effective removal of polycyclic aromatic hydrocarbons (PAHs) from the SWE. Furthermore, the sorption capabilities of organo-LDHs towards PHE and PYR at the higher loading amounts of SDS were much greater than that of commercial activated carbon at the higher concentration ranges of PAHs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Dodecyl sulfonate anion modified LDHs are employed for the removal of PHE and PYR in soil washing effluent (SWE). </LI> <LI> Organo-LDHs showed superior performance in PHE removal from SWE than that of commercial activated carbon. </LI> <LI> Partitioning of PHE and PYR in the organic fraction of the organo-LDHs was the main mechanism. </LI> <LI> Using organo-LDHs for the separation of HOCs from surfactants in SWE facilitated reuse of the surfactants. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Aging effects on chemical transformation and metal(loid) removal by entrapped nanoscale zero-valent iron for hydraulic fracturing wastewater treatment

Sun, Yuqing,Lei, Cheng,Khan, Eakalak,Chen, Season S.,Tsang, Daniel C.W.,Ok, Yong Sik,Lin, Daohui,Feng, Yujie,Li, Xiang-dong Elsevier 2018 Science of the Total Environment Vol.615 No.-

<P><B>Abstract</B></P> <P>In this study, alginate and polyvinyl alcohol (PVA)-alginate entrapped nanoscale zero-valent iron (nZVI) was tested for structural evolution, chemical transformation, and metals/metalloids removal (Cu(II), Cr(VI), Zn(II), and As(V)) after 1–2month passivation in model saline wastewaters from hydraulic fracturing. X-ray diffraction analysis confirmed successful prevention of Fe<SUP>0</SUP> corrosion by polymeric entrapment. Increasing ionic strength (<I>I</I>) from 0 to 4.10M (deionized water to Day-90 fracturing wastewater (FWW)) with prolonged aging time induced chemical instability of alginate due to dissociation of carboxyl groups and competition for hydrogen bonding with nZVI, which caused high Na (7.17%) and total organic carbon (24.6%) dissolution from PVA-alginate entrapped nZVI after 2-month immersion in Day-90 FWW. Compared to freshly-made beads, 2-month aging of PVA-alginate entrapped nZVI in Day-90 FWW promoted Cu(II) and Cr(VI) uptake in terms of the highest removal efficiency (84.2% and 70.8%), pseudo-second-order surface area-normalized rate coefficient <I>k</I> <SUB> <I>sa</I> </SUB> (2.09×10<SUP>−1</SUP> Lm<SUP>−2</SUP> h<SUP>−1</SUP> and 1.84×10<SUP>−1</SUP> Lm<SUP>−2</SUP> h<SUP>−1</SUP>), and Fe dissolution after 8-h reaction (13.9% and 8.45%). However, the same conditions inhibited Zn(II) and As(V) sequestration in terms of the lowest removal efficiency (31.2% and 39.8%) by PVA-alginate nZVI and <I>k</I> <SUB> <I>sa</I> </SUB> (4.74×10<SUP>−2</SUP> Lm<SUP>−2</SUP> h<SUP>−1</SUP> and 6.15×10<SUP>−2</SUP> Lm<SUP>−2</SUP> h<SUP>−1</SUP>) by alginate nZVI. The X-ray spectroscopic analysis and chemical speciation modelling demonstrated that the difference in metals/metalloids removal by entrapped nZVI after aging was attributed to distinctive removal mechanisms: (i) enhanced Cu(II) and Cr(VI) removal by nZVI reduction with accelerated electron transfer after pronounced dissolution of non-conductive polymeric immobilization matrix; (ii) suppressed Zn(II) and As(V) removal by nZVI adsorption due to restrained mass transfer after blockage of surface-active micropores. Entrapped nZVI was chemically fragile and should be properly stored and regularly replaced for good performance.</P> <P><B>Highlights</B></P> <P> <UL> <LI> nZVI entrapment successfully prevented Fe<SUP>0</SUP> corrosion in fracturing wastewaters. </LI> <LI> Entrapped nZVI was chemically fragile due to dissolution of Na and TOC. </LI> <LI> nZVI passivation promoted Cu(II) and Cr(VI) but inhibited Zn(II) and As(V) removal. </LI> <LI> Effects of nZVI aging on removal efficiency depended on interaction mechanisms. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Clinical Significance of Upregulation of mir-196a-5p in Gastric Cancer and Enriched KEGG Pathway Analysis of Target Genes

Li, Hai-Long,Xie, Shou-Pin,Yang, Ya-Li,Cheng, Ying-Xia,Zhang, Ying,Wang, Jing,Wang, Yong,Liu, Da-Long,Chen, Zhao-Feng,Zhou, Yong-Ning,Wu, Hong-Yan Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Background: miRNAs are relatively recently discovered cancer biomarkers which have important implications for cancer early diagnosis, treatment and estimation of prognosis. Here we focussed on expression of mir-196a-5p in gastric cancer tissues and cell lines so as to analyse its significance for clinicopathologic characteristics and generate enriched KEGG pathways clustered by target genes for exploring its potential roles as a biomarker in gastric cancer. Materials and Methods: The expression of mir-196a-5p in poorly, moderate and well differentiated gastric cancer cell lines compared with GES-1 was detected by RT-qPCR, and the expression of mir-196a-5p in gastric cancer tissues comparing with adjacent non cancer tissues of 58 cases were also assessed by RT-qPCR. Subsequently, an analysis of clinical significance of mir-196a-5p in gastric cancer and enriched KEGG pathways was executed based on the miRWalk prediction database combined with bioinformatics tools DAVID 6.7 and Mirfocus 3.0. Results: RT-qPCR showed that mir-196a-5p was up-regulated in 6 poorly and moderate differentiated gastric cancer cell lines SGC-7901, MKN-45, MKN-28, MGC-803, BGC-823, HGC-27 compared with GES-1, but down-regulated in the highly differentiated gastric cancer cell line AGS. Clinical data indicated mir-196a-5p to beup-regulated in gastric cancer tissues (47/58). Overexpression of mir-196a-5p was associated with more extensive degree of lymph node metastasis and clinical stage (P < 0.05; x2 test). Enriched KEGG pathway analyses of predicted and validated targets in miRWalk combined with DAVID 6.7 and Mirfocus 3.0 showed that the targeted genes regulated by mir-196a-5p were involved in malignancy associated biology. Conclusions: Overexpression of mir-196a-5p is associated with lymph node metastasis and clinical stage, and enriched KEGG pathway analyses showed that targeted genes regulated by mir-196a-5p may contribute to tumorgenesis, suggesting roles as an oncogenic miRNA biomarker in gastric cancer.

Deformation Characteristics and Countermeasures of shallow and Large-span Tunnel Under-crossing the Existing Highway in Soft Soil: a Case Study

Cheng-yong Cao,Cheng-hua Shi,Ming-feng Lei,Li-min Peng,Ruxue Bai 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.8

Hongmian Road goes under Jihe highway by the way of tunnel in Shenzhen City, Guangdong Province, China. The tunnel hassome special characteristics such as shallow depth, large span, soft soil, busy traffic, and long distance under-crossing the operatinghighway, thus there is great difficulty and risk during its construction. A series of in-situ tests were conducted to reveal deformationcharacteristics during tunneling beneath the existing highway by the double-side-drift method (DSDM). The results show that initialconstruction method and measures can't meet the safety requirement of tunnel construction, and the level of risk is extremely high, sothe construction method need to be timely adjusted. By comprehensive analysis, the double-side-drift optimum method (DSDOM) isput forward, on the basis of which a series of optimum measures also have been put forward, such as reasonable constructionmethods, the suitable length of bench and excavation, soil reinforcement measures on tunnel face, optimizing construction process,closing primary support in time and speeding up the construction of secondary lining. Then the feasibility of this optimizedconstruction method and measures are verified by the numerical simulations. Finally, from feedbacks of monitoring results, theoptimum method and measures have been proved to be reasonable and feasible, and they can guarantee a successful pass beneath theoperating highway.

Functional Magnetic Resonance Imaging in the Diagnosis of Locally Recurrent Prostate Cancer: Are All Pulse Sequences Helpful?

Xiao-Li Liao,Jun-Bao Wei,Yong-Qiang Li,Jian-Hong Zhong,Cheng-Cheng Liao,Chang-Yuan Wei 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.6

Objective: To perform a meta-analysis to quantitatively assess functional magnetic resonance imaging (MRI) in the diagnosis of locally recurrent prostate cancer. Materials and Methods: A comprehensive search of the PubMed, Embase, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews was conducted from January 1, 1995 to December 31, 2016. Diagnostic accuracy was quantitatively pooled for all studies by using hierarchical logistic regression modeling, including bivariate modeling and hierarchical summary receiver operating characteristic (HSROC) curves (AUCs). The Z test was used to determine whether adding functional MRI to T2-weighted imaging (T2WI) results in significantly increased diagnostic sensitivity and specificity. Results: Meta-analysis of 13 studies involving 826 patients who underwent radical prostatectomy showed a pooled sensitivity and specificity of 91%, and the AUC was 0.96. Meta-analysis of 7 studies involving 329 patients who underwent radiotherapy showed a pooled sensitivity of 80% and specificity of 81%, and the AUC was 0.88. Meta-analysis of 11 studies reporting 1669 sextant biopsies from patients who underwent radiotherapy showed a pooled sensitivity of 54% and specificity of 91%, and the AUC was 0.85. Sensitivity after radiotherapy was significantly higher when diffusion-weighted MRI data were combined with T2WI than when only T2WI results were used. This was true when meta-analysis was performed on a per-patient basis (p = 0.027) or per sextant biopsy (p = 0.046). A similar result was found when 1H-magnetic resonance spectroscopy (1H-MRS) data were combined with T2WI and sextant biopsy was the unit of analysis (p = 0.036). Conclusion: Functional MRI data may not strengthen the ability of T2WI to detect locally recurrent prostate cancer in patients who have undergone radical prostatectomy. By contrast, diffusion-weight MRI and 1H-MRS data may improve the sensitivity of T2WI for patients who have undergone radiotherapy.

Identification of Specific Gene Modules in Mouse Lung Tissue Exposed to Cigarette Smoke

Xing, Yong-Hua,Zhang, Jun-Ling,Lu, Lu,Li, De-Guan,Wang, Yue-Ying,Huang, Song,Li, Cheng-Cheng,Zhang, Zhu-Bo,Li, Jian-Guo,Xu, Guo-Shun,Meng, Ai-Min Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.10

Background: Exposure to cigarette may affect human health and increase risk of a wide range of diseases including pulmonary diseases, such as chronic obstructive pulmonary disease (COPD), asthma, lung fibrosis and lung cancer. However, the molecular mechanisms of pathogenesis induced by cigarettes still remain obscure even with extensive studies. With systemic view, we attempted to identify the specific gene modules that might relate to injury caused by cigarette smoke and identify hub genes for potential therapeutic targets or biomarkers from specific gene modules. Materials and Methods: The dataset GSE18344 was downloaded from the Gene Expression Omnibus (GEO) and divided into mouse cigarette smoke exposure and control groups. Subsequently, weighted gene co-expression network analysis (WGCNA) was used to construct a gene co-expression network for each group and detected specific gene modules of cigarette smoke exposure by comparison. Results: A total of ten specific gene modules were identified only in the cigarette smoke exposure group but not in the control group. Seven hub genes were identified as well, including Fip1l1, Anp32a, Acsl4, Evl, Sdc1, Arap3 and Cd52. Conclusions: Specific gene modules may provide better understanding of molecular mechanisms, and hub genes are potential candidates of therapeutic targets that may possible improve development of novel treatment approaches.

Analysis of Bacterial Diversity and Communities Associated with Tricholoma matsutake Fruiting Bodies by Barcoded Pyrosequencing in Sichuan Province, Southwest China

( Qiang Li ),( Xiao Lin Li ),( Cheng Chen ),( Shu Hong Li ),( Wen Li Huang ),( Chuan Xiong ),( Xing Jin ),( Lin Yong Zheng ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.1

Endophytes play an important role in the growth and development of the host. However, the study of endophytes is mostly focused on plants, and reports on bacteria associated with fungi are relatively rare. We studied the bacteria associated with fruiting bodies of Tricholoma matsutake picked from seven main T. matsutake-producing areas in Sichuan, China, by barcoded pyrosequencing. About 8,272 reads were obtained per sample, representing 40 phyla, 103 classes, and 495 genera of bacteria and archaea, and 361.797 operational taxonomic units were observed at a 97% similarity level. The bacterial community was always both more abundant and more diverse than the archaeal community. UniFrac analysis showed there were some difference of bacterial communities among the samples sites. Three bacterial phyla, Proteobacteria, Bacteroidetes, and Firmicutes, were dominant in all samples. Correlation analysis showed there was a significant correlation between some soil properties and bacterial community associated with T. matsutake. This study demonstrated that the bacteria associated with T. matsutake fruiting bodies were diversified. Among these bacteria, we may find some strains that can promote the growth of T. matsutake.

Low-dose diethylhexyl phthalate exposure does not impair the expressive patterns of epigenetics-related genes and DNA methylation of breast cancer-related genes in mouse mammary glands

Shun-Feng Cheng,Ling Li,Bo Li,Jing-Cai Liu,Fang-Nong Lai,Yong Zhao,Xi-Feng Zhang,Wei Shen,Lan Li 대한독성 유전단백체 학회 2018 Molecular & cellular toxicology Vol.14 No.2

Backgrounds: Di-(2-ethylhexyl) phthalate (DEHP), as an endocrine-disrupting chemical (EDC), is widely used in plasticizer and other productions. Ubiquitous human exposure to DEHP has been proposed to be a potential risk to public health. Developmental exposure to DEHP could alter epigenetic programming and result in adult-onset disease. Methods: In this study, we investigated whether DEHP exposure to pregnant mice affected epigenetic changes as a result of increase in breast cancer incidence. Results: Our results showed that the expression of total 143 epigenetics-related genes in mammary gland cells, have no significantly altered after short time and low-dose treated with DEHP from 0.5 days post-coitum (dpc) to 3.5 dpc of pregnant mice. DNA methylation status of some neoplastic development genes, such as EGFr, Esr1, Pgr, Fos and Rassf5 also had no obvious change. Conclusion: These finding showed no impact of DEHP on the expressive patterns of epigenetics-related genes and DNA methylation of breast cancer-related genes in pregnant mouse mammary gland cells.