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期刊论文 44

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Efficient promotion of methane hydrate formation and elimination of foam generation using fluorinated surfactants

Quan CAO, Dongyan XU, Huanfei XU, Shengjun LUO, Rongbo GUO

《能源前沿（英文）》 2020年 第14卷 第3期   页码 443-451 doi: 10.1007/s11708-020-0683-2

摘要： Methane hydrate preparation is an effective method to store and transport methane. In promoters to facilitate methane hydrate formation, homogeneous surfactant solutions, sodium dodecyl sulfate (SDS) in particular, are more favorable than heterogeneous particles, thanks to their faster reaction rate, more storage capacity, and higher stability. Foaming, however, could not be avoided during hydrate dissociation with the presence of SDS. This paper investigated the ability of five fluorinated surfactants: potassium perfluorobutane sulfonate (PBS), potassium perfluorohexyl sulfonate (PHS), potassium perfluorooctane sulfonate (POS), ammonium perfluorooctane sulfonate (AOS), and tetraethylammonium perfluorooctyl sulfonate (TOS) to promote methane hydrate formation. It was found that both PBS and PHS achieve a storage capacity of 150 ( , the volume of methane that can be stored by one volume of water) within 30 min, more than that of SDS. Cationic ions and the carbon chain length were then discussed on their effects during the formation. It was concluded that PBS, PHS, and POS produced no foam during hydrate dissociation, making them promising promoters in large-scale application.

关键词： methane hydrate     fluorinated surfactants     homogeneous promoter     foam elimination     stability    

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Effect of a promoter on the methanation activity of a Mo-based sulfur-resistant catalyst

Can LIN, Haiyang WANG, Zhenhua LI, Baowei WANG, Xinbin MA, Shaodong QIN, Qi SUN

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 88-94 doi: 10.1007/s11705-013-1301-1

摘要： The effect of adding Co, Ni or La on the methanation activity of a Mo-based sulfur-resistant catalyst was investigated. As promoters, Co, Ni and La all improved the methanation activity of a 15% MoO /Al O catalyst but to different extents. Similar improvements were also found when Co, Ni or La was added to a 15% MoO /25%-CeO -Al O catalyst. The promotion effects of Co and Ni were better than that of La. However, the catalytic methanation activity deteriorated the most with time for the Ni-promoted catalyst. The used catalysts were analyzed by nitrogen adsorption measurement, X-ray diffraction and X-ray photoelectron spectroscopy.

关键词： sulfur-resistant     methanation     promoter    

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Effect of a less permeable stronger soil layer on the stability of non-homogeneous unsaturated slopes

Nabarun DEY, Aniruddha SENGUPTA

《结构与土木工程前沿（英文）》 2020年 第14卷 第6期   页码 1462-1475 doi: 10.1007/s11709-020-0674-8

摘要： Slope failure occurs due to an increase in the saturation level and a subsequent decrease in matric suction in unsaturated soil. This paper presents the results of a series of centrifuge experiments and numerical analyses on a 55° inclined unsaturated sandy slope with less permeable, stronger silty sand layer inclusion within it. It is observed that a less permeable, stronger silty sand layer in an otherwise homogeneous sandy soil slope hinders the infiltration of water. The water content of the slope just above the stronger layer increases significantly, compared to elsewhere. No shear band is found to initiate in a homogeneous sandy soil slope, whereas for a non-homogeneous slope, they initiate just above the less pervious, stronger layer. A discontinuity of the shear zone is also observed for the case of a non-homogeneous soil slope. The factor of safety of a non-homogeneous, unsaturated soil slope decreases because of the less permeable, stronger layer. It decreases significantly if this less permeable, stronger soil layer is located near the toe of the slope.

关键词： non-homogeneous slope     stronger soil layer     factor of safety     centrifuge model test     unsaturated soils    

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Control of homogeneous charge compression ignition combustion in a two-cylinder gasoline direct injection

WANG Zhi, WANG Jianxin, SHUAI Shijin, MA Qingjun, TIAN Guohong

《能源前沿（英文）》 2007年 第1卷 第3期   页码 311-315 doi: 10.1007/s11708-007-0045-3

摘要： Homogeneous charge compression ignition (HCCI) has challenges in ignition timing control, combustion rate control, and operating range extension. In this paper, HCCI combustion was studied in a two-cylinder gasoline direct injection (GDI) engine with negative valve overlap (NVO). A two-stage gasoline direct injection strategy combined with negative valve overlap was used to control mixture formation and combustion. The gasoline engine could be operated in HCCI combustion mode at a speed range of 800–2 200 r/min and load, indicated mean effective pressure (IMEP) range of 0.1–0.53 MPa. The engine fuel consumption is below 240 g/(kW

关键词： Homogeneous     control     combustion     consumption     extension    

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Osteopontin is a promoter for hepatocellular carcinoma metastasis: a summary of 10 years of studies

null

《医学前沿（英文）》 2014年 第8卷 第1期   页码 24-32 doi: 10.1007/s11684-014-0312-8

摘要：

In this review, we summarize the novel findings from our series of studies on the leading metastasis-related gene, osteopontin (OPN). In our previous gene expression profiling study, OPN was identified as one of the leading genes associated with the metastasis of hepatocellular carcinoma (HCC). We focused on OPN to evaluate its prognostic values and important roles in HCC metastasis. A retrospective study of large cohorts of HCC patients demonstrated that plasma OPN level was one of the leading independent prognostic factors for HCC patients, even in the early stage of HCC, and could serve as a surrogate serologic biomarker for monitoring the treatment response and tumor recurrence after HCC resection. Using both in vitro and in vivoinvestigations, we found that OPN has an important role in metastasis and tumor growth of HCC and is an attractive potential therapeutic target for combating HCC metastasis. We also found that OPN+ HCC cells have much more amplifications at chromosomal regions, and promoter polymorphisms are important in the regulation of OPN expression and tumor growth and lung metastasis of HCC.

关键词： osteopontin (OPN)     hepatocellular carcinoma     metastasis     prognosis     therapeutic target     biomarker     genetic polymorphism    

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Cloning of human XAF1 gene promoter and assay of its transcription activity in a variety of cell lines

Qiong CHEN, Qing YU, Yuhu SONG, Peiyuan Li, Ying CHANG, Zhijun WANG, Lifeng LIU, Wei WU, Jusheng LIN

《医学前沿（英文）》 2009年 第3卷 第2期   页码 148-152 doi: 10.1007/s11684-009-0032-7

摘要： To investigate the regulation of tumor suppressor XAF1 gene expression in digestive system cancers, we studied XAF1 gene promoter transcription activity and mRNA level in digestive system cancer cell lines (human hepatoma cell line HepG2, human colon cancer cell line LoVo, and human gastric cancer cell line AGS) and nontumor cell lines (human embryonic liver cell line L02 (L02 cells) and human embryonic kidney 293 cells [HEK293 cells]) as controls. 1395-bp-promoter fragment of XAF1 gene was amplified by polymerase chain reaction (PCR) and cloned into pGL3-basic vector and pEGFP-1 vector to assay its promoter transcription activity. The plasmids were transfected into a variety of cell lines by lipofectamine 2000. The promoter transcription activity was determined by dual-luciferase report assay, and enhanced green fluorescent protein (EGFP)-positive cells were detected by fluorescence microscope. The expression of XAF1 mRNA in HEK293 and L02 were significantly higher than that in any of the three digestive system cancer cell lines. The dual-luciferase reporter assay showed that the promoter transcription activity in digestive system tumor cell lines transfected with pGL3-XAF1p promoter was apparently lower than that of both HEK293 and L02 cells. Expression of green fluorescent protein (GFP) under the control of XAF1 promoter in the three digestive system cancer cell lines was lower than that of both HEK293 and L02 cells. The activities of pGL3-XAF1p in the three digestive system cancer cell lines after treatment with heat stress were significantly lower than those in the unstressed cells. The results suggested that remarkably down-regulated XAF1 mRNA expression in digestive system cancer cell lines may be due to loss of transcription activity of XAF1 promoter.

关键词： gene     X-linked inhibitor of apoptosis protein associated factor-1 (XAF1)     promoter     transcription regulation    

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Liquid discharge plasma for fast biomass liquefaction at mild conditions: The effects of homogeneous

Sen Wang, Shiyun Liu, Danhua Mei, Rusen Zhou, Congcong Jiang, Xianhui Zhang, Zhi Fang, Kostya (Ken) Ostrikov

《化学科学与工程前沿（英文）》 2020年 第14卷 第5期   页码 763-771 doi: 10.1007/s11705-019-1896-y

摘要： Non-thermal plasma exhibits unique advantages in biomass conversion for the sustainable production of higher-value energy carriers. Different homogeneous catalysts are usually required for plasma-enabled biomass liquefaction to achieve time-and energy-efficient conversions. However, the effects of such catalysts on the plasma-assisted liquefaction process and of the plasma on those catalysts have not been thoroughly studied. In this study, an electrical discharge plasma is employed to promote the direct liquefaction of sawdust in a mixture of polyethylene glycol 200 and glycerol. Three commonly used chemicals, sulfuric acid, nitric acid and sodium -toluene sulfate, were selected as catalysts. The effects of the type of catalyst and concentration on the liquefaction yield were examined; further, the roles of the catalysts in the plasma liquefaction process have been discussed. The results showed that the liquefaction yield attains a value of 90% within 5 min when 1% sulfuric acid was employed as the catalyst. Compared with the other catalysts, sulfuric acid presents the highest efficiency for the liquefaction of sawdust. It was observed that hydrogen ions from the catalyst were primarily responsible for the significant thermal effects on the liquefaction system and the generation of large quantities of active species; these effects directly contributed to a higher efficacy of the plasma-enabled liquefaction process.

关键词： discharge plasma     biomass liquefaction     catalyst     homogeneous catalysts    

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Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation

《医学前沿（英文）》 2022年 第16卷 第4期   页码 627-636 doi: 10.1007/s11684-020-0815-4

摘要： Runt-related transcription factor 1 (RUNX1) is an essential regulator of normal hematopoiesis. Its dysfunction, caused by either fusions or mutations, is frequently reported in acute myeloid leukemia (AML). However, RUNX1 mutations have been largely under-explored compared with RUNX1 fusions mainly due to their elusive genetic characteristics. Here, based on 1741 patients with AML, we report a unique expression pattern associated with RUNX1 mutations in AML. This expression pattern was coordinated by target repression and promoter hypermethylation. We first reanalyzed a joint AML cohort that consisted of three public cohorts and found that RUNX1 mutations were mainly distributed in the Runt domain and almost mutually exclusive with NPM1 mutations. Then, based on RNA-seq data from The Cancer Genome Atlas AML cohort, we developed a 300-gene signature that significantly distinguished the patients with RUNX1 mutations from those with other AML subtypes. Furthermore, we explored the mechanisms underlying this signature from the transcriptional and epigenetic levels. Using chromatin immunoprecipitation sequencing data, we found that RUNX1 target genes tended to be repressed in patients with RUNX1 mutations. Through the integration of DNA methylation array data, we illustrated that hypermethylation on the promoter regions of RUNX1-regulated genes also contributed to dysregulation in RUNX1-mutated AML. This study revealed the distinct gene expression pattern of RUNX1 mutations and the underlying mechanisms in AML development.

关键词： RUNX1     gene mutation     acute myeloid leukemia     transcriptional repression     DNA methylation    

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Effects of compression ratio on the combustion characteristics of a homogeneous charge compression ignition

SONG Ruizhi, ZHOU Longbao, LIU Shenghua, LI Wei, HU Tiegang

《能源前沿（英文）》 2007年 第1卷 第4期   页码 463-467 doi: 10.1007/s11708-007-0068-0

摘要： The effects of homogeneous charge compression ignition (HCCI) engine compression ratio on its combustion characteristics were studied experimentally on a modified TY1100 single cylinder engine fueled with dimethyl ether. The resul

关键词： homogeneous     cylinder     combustion     compression     dimethyl    

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Construction, characterization and application of a genome-wide promoter library in

Ting Yuan,Yakun Guo,Junkai Dong,Tianyi Li,Tong Zhou,Kaiwen Sun,Mei Zhang,Qingyu Wu,Zhen Xie,Yizhi Cai,Limin Cao,Junbiao Dai

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 107-116 doi: 10.1007/s11705-017-1621-7

摘要： Promoters are critical elements to control gene expression but could behave differently under various growth conditions. Here we report the construction of a genome-wide promoter library, in which each native promoter in was cloned upstream of a yellow fluorescent protein (YFP) reporter gene. Nine libraries were arbitrarily defined and assembled in bacteria. The resulting pools of promoters could be prepared and transformed into a yeast strain either as centromeric plasmids or integrated into a genomic locus upon enzymatic treatment. Using fluorescence activated cell sorting, we classified the yeast strains based on YFP fluorescence intensity and arbitrarily divided the entire library into 12 bins, representing weak to strong promoters. Several strong promoters were identified from the most active bins and their activities were assayed under different growth conditions. Finally, these promoters were applied to drive the expression of genes in xylose utilization to improve fermentation efficiency. Together, this library could provide a quick solution to identify and utilize desired promoters under user-defined growth conditions.

关键词： synthetic biology     yeast     promoter activity     metabolic engineering     xylose utilization    

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Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 167-171 doi: 10.1007/s11705-007-0031-7

摘要： The effects of MgO promoter on the physico-chemical properties and catalytic performance of Ni/AlO catalysts for the partial oxidation of methane to syngas were studied by means of BET, XRD, H-TPR, TEM and performance evaluation. It was found that the MgO promoter benefited from the uniformity of nickel species in the catalysts, inhibited the formation of NiAlO spinel and improved the interaction between nickel species and support. These results were related to the formation of NiO MgO solid solution and MgAlO spinel. Moreover, for the catalysts with a proper amount of MgO promoter, the nickel dispersiveness was enhanced, therefore making their catalytic performance in methane partial oxidation improved. However, the excessive MgO promoter exerted a negative effect on the catalytic performance. Meanwhile, the basicity of MgO promoted the reversed water gas shift reaction, which led to an increase in CO selectivity and a decrease in H2 selectivity. The suitable content of MgO promoter in Ni/AlO catalyst was ?7 wt-%.

关键词： excessive     selectivity     decrease     dispersiveness     physico-chemical    

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Reactive adsorption desulfurization over a Ni/ZnO adsorbent prepared by homogeneous precipitation

Aihua KONG, Yanyu WEI, Yonghong LI

《化学科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 170-176 doi: 10.1007/s11705-013-1322-9

摘要： A high-performance Ni/ZnO adsorbent was prepared by homogeneous precipitation using urea hydrolysis and characterized by N adsorption-desorption, X-ray diffraction (XRD), and scanning electron microscope (SEM). The adsorbent was applied to the deep desulfurization of gasoline and showed a high breakthrough sulfur capacity and a remarkably high volume hourly space velocity. The effects of coexisting olefins in gasoline as well as adsorptive conditions on the adsorptive performance were examined. It was found that olefins in gasoline had a slightly inhibiting effect on the desulfurization performance of the adsorbent. The optimum conditions were 673 K, 1.0 Mpa with a volume hourly space velocity of 60 h . Under the optimum conditions, ultralow sulfur gasoline could be produced and the breakthrough sulfur capacity of the adsorbent was 360 mg-s/g-sorb for the model gasoline.

关键词： nickel     reactive adsorption     desulfurization     thiophene    

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Progress in use of surfactant in nearly static conditions in natural gas hydrate formation

Zhen PAN, Yi WU, Liyan SHANG, Li ZHOU, Zhien ZHANG

《能源前沿（英文）》 2020年 第14卷 第3期   页码 463-481 doi: 10.1007/s11708-020-0675-2

摘要： Natural gas hydrate is an alternative energy source with a great potential for development. The addition of surfactants has been found to have practical implications on the acceleration of hydrate formation in the industrial sector. In this paper, the mechanisms of different surfactants that have been reported to promote hydrate formation are summarized. Besides, the factors influencing surfactant-promoted hydrate formation, including the type, concentration, and structure of the surfactant, are also described. Moreover, the effects of surfactants on the formation of hydrate in pure water, brine, porous media, and systems containing multiple surfactants are discussed. The synergistic or inhibitory effects of the combinations of these additives are also analyzed. Furthermore, the process of establishing kinetic and thermodynamic models to simulate the factors affecting the formation of hydrate in surfactant-containing solutions is illustrated and summarized.

关键词： gas hydrate     kinetic hydrate promoter     compounding     model     surfactant     mechanism    

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钾/锰助剂对氮掺杂碳纳米管负载铁基催化剂在CO2加氢过程中的影响研究 Article

Praewpilin Kangvansura, Ly May Chew, Chanapa Kongmark, Phatchada Santawaja, Holger Ruland, Wei Xia, Hans Schulz, Attera Worayingyong, Martin Muhler

《工程（英文）》 2017年 第3卷 第3期   页码 385-392 doi: 10.1016/J.ENG.2017.03.013

摘要：

氮掺杂碳纳米管(NCNTs) 作为载体负载铁(Fe) 纳米颗粒，可应用于CO2多相催化加氢反应(633 K和25 bar)。当将钾(K) 和锰(Mn) 作为助催化剂时，Fe/NCNT 展现出优异的CO2 加氢性能，在体积空速(GHSV) 为3.1 L·(g·h)–1 时转化率可达34.9%。当使用K 作为助催化剂时，反应对烯烃和短链烷烃具有高的选择性。当K 和Mn 同时作为助催化剂时，其催化活性能够稳定地维持60 h。助催化剂Mn 的结构效应通过X 射线衍射、氢气程序升温还原以及近边X 射线吸收精细结构进行表征。助催化剂Mn 不仅能够稳定中间态FeO，且能降低程序升温还原的起始温度。通过探针反应NH3 的催化分解来表征助催化剂效应。当K 和Mn 作为助催化剂时，Fe/NCNT 具有最好的催化活性。在还原条件下，当K 作为助催化剂时，Fe/NCNT 具有最优异的热稳定性。

关键词： CO2 加氢     铁基催化剂     n 型碳纳米管     Mn 助剂     K 助剂    

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Methanol to propylene: the effect of iridium and iron incorporation on the HZSM-5 catalyst

Alireza MOHAMMADREZAEI, Sadegh PAPARI, Mousa ASADI, Abas NADERIFAR, Reza GOLHOSSEINI

《化学科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 253-258 doi: 10.1007/s11705-012-0902-4

摘要： The effect of iridium and iron impregnation of HZSM-5 zeolite on the methanol to propylene reaction (MTP) was investigated. The selectivities of propylene and other hydrocarbons, and the conversion of methanol were compared by performing MTP in a small pilot plant. The results indicate that HZSM-5 zeolite modified by iron and iridium increased propylene selectivity by 6.3% and 8%, respectively. The selectivity of propylene was higher for Ir/H-ZSM-5 than for Fe/H-ZSM-5, where Fe/H-ZSM-5 was more stable than Ir/H-ZSM-5. Analytic techniques, including X-ray diffraction, BET surface area, temperature-programmed desorption of ammonia, and inductively coupled plasma atomic emission spectroscopy, were used to characterize the modified zeolites as well as the parent zeolites.

关键词： HZSM-5     promoter     iridium     iron     MTP    

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标题 作者 时间 类型 操作

Efficient promotion of methane hydrate formation and elimination of foam generation using fluorinated surfactants

Quan CAO, Dongyan XU, Huanfei XU, Shengjun LUO, Rongbo GUO

期刊论文

Effect of a promoter on the methanation activity of a Mo-based sulfur-resistant catalyst

Can LIN, Haiyang WANG, Zhenhua LI, Baowei WANG, Xinbin MA, Shaodong QIN, Qi SUN

期刊论文

Effect of a less permeable stronger soil layer on the stability of non-homogeneous unsaturated slopes

Nabarun DEY, Aniruddha SENGUPTA

期刊论文

Control of homogeneous charge compression ignition combustion in a two-cylinder gasoline direct injection

WANG Zhi, WANG Jianxin, SHUAI Shijin, MA Qingjun, TIAN Guohong

期刊论文

Osteopontin is a promoter for hepatocellular carcinoma metastasis: a summary of 10 years of studies

null

期刊论文

Cloning of human XAF1 gene promoter and assay of its transcription activity in a variety of cell lines

Qiong CHEN, Qing YU, Yuhu SONG, Peiyuan Li, Ying CHANG, Zhijun WANG, Lifeng LIU, Wei WU, Jusheng LIN

期刊论文

Liquid discharge plasma for fast biomass liquefaction at mild conditions: The effects of homogeneous

Sen Wang, Shiyun Liu, Danhua Mei, Rusen Zhou, Congcong Jiang, Xianhui Zhang, Zhi Fang, Kostya (Ken) Ostrikov

期刊论文

Distinct gene expression pattern of mutations coordinated by target repression and promoter hypermethylation

期刊论文

Effects of compression ratio on the combustion characteristics of a homogeneous charge compression ignition

SONG Ruizhi, ZHOU Longbao, LIU Shenghua, LI Wei, HU Tiegang

期刊论文

Construction, characterization and application of a genome-wide promoter library in

Ting Yuan,Yakun Guo,Junkai Dong,Tianyi Li,Tong Zhou,Kaiwen Sun,Mei Zhang,Qingyu Wu,Zhen Xie,Yizhi Cai,Limin Cao,Junbiao Dai

期刊论文

Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

期刊论文

Reactive adsorption desulfurization over a Ni/ZnO adsorbent prepared by homogeneous precipitation

Aihua KONG, Yanyu WEI, Yonghong LI

期刊论文

Progress in use of surfactant in nearly static conditions in natural gas hydrate formation

Zhen PAN, Yi WU, Liyan SHANG, Li ZHOU, Zhien ZHANG

期刊论文

钾/锰助剂对氮掺杂碳纳米管负载铁基催化剂在CO2加氢过程中的影响研究

Praewpilin Kangvansura, Ly May Chew, Chanapa Kongmark, Phatchada Santawaja, Holger Ruland, Wei Xia, Hans Schulz, Attera Worayingyong, Martin Muhler

期刊论文

Methanol to propylene: the effect of iridium and iron incorporation on the HZSM-5 catalyst

Alireza MOHAMMADREZAEI, Sadegh PAPARI, Mousa ASADI, Abas NADERIFAR, Reza GOLHOSSEINI

期刊论文