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Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on

GUO Ting, BAI Zhipeng, WU Can, ZHU Tan

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 224-229 doi: 10.1007/s11783-008-0039-3

摘要： TiO supported on active carbon fiber (TiO/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO/ACF were studied, and then, the purification capability of TiO/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH = 30% is the optimal condition for purifying toluene in our experimental system.

关键词： application     gas-solid adsorption     technique     TiO/ACF     experimental    

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Modeling of coal swelling induced by water vapor adsorption

Zhejun PAN

《化学科学与工程前沿（英文）》 2012年 第6卷 第1期   页码 94-103 doi: 10.1007/s11705-011-1172-2

摘要： Gas adsorption-induced coal swelling is a well-know phenomenon. Coal swelling or shrinkage by adsorption or desorption of water vapor has not been well understood but has significant implications on gas drainage process for underground coal mining and for primary and enhanced coalbed methane production. Decreased matrix moisture content leads to coal shrinkage and thus the change of cleat porosity and permeability under reservoir conditions. Unlike gas adsorption in coal which usually forms a single layer of adsorbed molecules, water vapor adsorption in the coal micropores forms multilayer of adsorbed molecules. In this work, a model has been developed to describe the coal swelling strain with respect to the amount of moisture intake by the coal matrix. The model extended an energy balance approach for gas adsorption-induced coal swelling to water vapor adsorption-induced coal swelling, assuming that only the first layer of adsorbed molecules of the multilayer adsorption changes the surface energy, which thus causes coal to swell. The model is applied to describe the experimental swelling strain data measured on an Australian coal. The results show good agreement between the model and the experimental data.

关键词： multilayer adsorption     vapour pressure     coal shrinkage     relative humidity     permeability    

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Organic nitrogen in PM

Qian ZHANG,Fengkui DUAN,Kebin HE,Yongliang MA,Haiyan LI,Takashi KIMOTO,Aihua ZHENG

《环境科学与工程前沿（英文）》 2015年 第9卷 第6期   页码 1004-1014 doi: 10.1007/s11783-015-0799-5

摘要： Nitrogenous species, as important chemical components in PM , include organic nitrogen (ON) and inorganic nitrogen (IN), both of which have potential effects on human health, climate change and visibility degradation. In this study, we analyzed total nitrogen (TN) by CHN Elemental analyzer and inorganic nitrogen by ion chromatography (IC) respectively to obtain ON by calculating the difference between TN and IN. The results show that the mean ON concentrations in winter and summer are both 2.86 μg·m , ten times higher than other places reported on average. ON contributes about 20%–30% to TN on average in both seasons, presenting higher contribution in summer. N:C ratios are much higher in summer than winter. ON sources or formation were strengthened by heavy PM pollution loads, especially sensitive to sulfate. ON concentrations are higher at night in the both seasons, however with distinguished day and night difference patterns influenced by relative humidity (RH) conditions. In winter, ON concentrations increase with RH on average through low RH values to high RH values. The variations are far larger than the ones caused by day and night difference. However in summer, day and night difference dominates the variations of ON concentrations at low RH values, and RH conditions promote ON concentrations increase significantly only at high RH values. Dust related source and anthropogenic emission related secondary source are identified as important sources for ON. At heavy pollution loads, ON sources are more of secondary formation, possibly strengthened by combination influence of RH and acidity increase.

关键词： organic nitrogen     N:C ratio     secondary     day and night variation     relative humidity (RH)     acidity    

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Abatement of mixed volatile organic compounds in a catalytic hybrid surface/packed-bed discharge plasma reactor

Lianjie Guo, Nan Jiang, Jie Li, Kefeng Shang, Na Lu, Yan Wu

《环境科学与工程前沿（英文）》 2018年 第12卷 第2期 doi: 10.1007/s11783-018-1017-z

摘要： In this study, post plasma-catalysis degradation of mixed volatile organic compounds (benzene, toluene, and xylene) has been performed in a hybrid surface/packed-bed discharge plasma reactor with Ag-Ce/ g-Al O catalyst at room temperature. The effect of relative air humidity on mixed VOCs degradation has also been investigated in both plasma-only and PPC systems. In comparison to the plasma-only system, a significant improvement can be observed in the degradation performance of mixed VOCs in PPC system with Ag-Ce/ g-Al O catalyst. In PPC system, 68% benzene, 89% toluene, and 94% xylene were degraded at 800 J·L , respectively, which were 25%, 11%, and 9% higher than those in plasma-only system. This result can be attributed to the high catalytic activity of Ag-Ce/ g-Al O catalyst to effectively decompose O and lead to generating more reactive species which are capable of destructing the VOCs molecules completely. Moreover, the presence of Ag-Ce/ g-Al O catalyst in plasma significantly decreased the emission of discharge byproducts (NO and O ) and promoted the mineralization of mixed VOCs towards CO . Adding a small amount of water vapor into PPC system enhanced the degradation efficiencies of mixed VOCs, however, further increasing water vapor had a negative impact on the degradation efficiencies, which was primarily attributed to the quenching of energetic electrons by water vapor in plasma and the competitive adsorption of water vapor on the catalyst surface. Meanwhile, the catalysts before and after discharge were characterized by the Brunauer-Emment-Teller and X-ray photoelectron spectroscopy.

关键词： Mixed VOCs     HSPBD plasma reactor     Degradation     Catalyst     Relative humidity    

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EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

《农业科学与工程前沿（英文）》 2023年 第10卷 第1期   页码 61-72 doi: 10.15302/J-FASE-2022476

摘要：

● Promotion of local sustainable innovation developed by forest farmers.

关键词： agroforestry     forest farmers     local innovation     relative advantage     social forestry    

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Measurement of bone alkaline phosphatase and relative study with osteosarcoma

YANG Zhiping, LI Jianmin, LI Xin, HUO Yanqing, SUN Guangzhi

《医学前沿（英文）》 2007年 第1卷 第1期   页码 54-57 doi: 10.1007/s11684-007-0011-9

摘要： The objective of this paper is to explore the value of bone alkaline phosphatase (BALP) for diagnosing osteosarcoma, evaluating the effect of the chemotherapy, judging the prognosis and supervising the relapse and metastasis. The immunoassay was used to check the BALP of the blood serum that was from 42 primary osteosarcoma patients. Alkaline phosphatase (ALP) in blood serum was checked with auto biochemistry equipment. The biopsy tissue and the lesion resected in operation were treated with pathology and histological response was counted. The patients were followed up from five months to 49 months with an average of 24.3 months. Eighteen cases relapsed and transferred, among which, 16 of them were dead, and others were survival to the end of the follow-up. BALP was more sensitive than ALP in diagnosing osteosarcoma ( = 0.015). Fifteen cases decreased to normal value in ALP after preoperative chemotherapy, and 34 cases decreased in BALP. Both ALP and BALP in all cases decreased to normal value in postoperative. There was significant difference in positive correlation between the decrease of BALP and the increase of histological response ( = 0.001, = 0.642). In the followup, there was significant difference in BALP between the group of relapse and transfer and the group of free disease survival ( = 0.000). As a check marker in blood serum, BALP, reflecting the process of ossification, has a higher sensitivity than ALP. It has applied value in the diagnosis of osteosarcoma, reflection of the effect of chemotherapy and forecast the prognosis.
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Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic

HUANG Jiuyi, WANG Guiqing, GUO Jiping, CAO Yifeng, WANG Yan, YANG Yongju, YU Xuehai

《医学前沿（英文）》 2007年 第1卷 第3期   页码 274-278 doi: 10.1007/s11684-007-0052-0

摘要： The relative risk (RR) of stroke in patients with hypertension was evaluated by using synthetic index of cerebrovascular hemodynamics. A total of 7,371 patients with hypertension with ages ≥40 years were selected from a population-based cohort study of the risk factors for stroke. The data on the baseline investigation of risk factors, the determination of cerebrovascular hemodynamic parameters (CVHP), and stroke follow-up were analyzed. The RR of stroke in patients with hypertension was evaluated by CVHP scores. Univariate analysis indicated that hypertension, complicated by other risk factors, had significant statistical association with the onset of stroke. RRs for stroke when hypertension complicated with decrease of hemodynamic scores, heart disease, cigarette smoking and alcohol consumption were 4.93 (95%CI, 3.26–7.45), 1.90 (95%CI, 1.36–2.66), 1.99 (95%CI, 1.42–2.79) and 1.73 (95%CI, 1.19–2.53) respectively. In multivariate analysis, hemodynamic score, age, sex, cigarette smoking, family history of stroke and systolic blood pressure were selected by the Cox regression for inclusion in the final analysis. Among them, the RR of hemodynamic score was highest. The analysis of doseresponse relationships indicated that when the hemodynamic scores in patients with hypertension were lower than 75 points, the RR of stroke at 75, 60, 45, 30 and 15 points were 2.85, 4.43, 4.54, 5.40 and 9.88, respectively. The risk of stroke in patients with hypertension is closely asso ciated with hemodynamic impairment and the hemodynamic score may be used for quantitative evaluation of relative risks of stroke.

关键词： inclusion     quantitative evaluation     cerebrovascular     relative     decrease    

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palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction: Impact of relative

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

《环境科学与工程前沿（英文）》 2020年 第14卷 第2期 doi: 10.1007/s11783-019-1206-4

摘要： • Pd nanoparticles could be reduced and supported by activated sludge microbes. • The effect of biomass on Pd adsorption by microbes is greater than Pd reduction. • More biomass reduces Pd particle size, which is more dispersed on the cell surface. • When the biomass/Pd add to 6, the catalytic reduction rate of Cr(VI) reaches stable. Palladium, a kind of platinum group metal, owns catalytic capacity for a variety of hydrogenations. In this study, Pd nanoparticles (PdNPs) were generated through enzymatic recovery by microbes of activated sludge at various biomass/Pd, and further used for the Cr(VI) reduction. The results show that biomass had a strong adsorption capacity for Pd(II), which was 17.25 mg Pd/g sludge. The XRD and TEM-EDX results confirmed the existence of PdNPs associated with microbes (bio-Pd). The increase of biomass had little effect on the reduction rate of Pd(II), but it could cause decreasing particle size and shifting location of Pd(0) with the better dispersion degree on the cell surface. In the Cr(VI) reduction experiments, Cr(VI) was first adsorbed on bio-Pd with hydrogen and then reduced using active hydrogen as electron donor. Biomass improved the catalytic activity of PdNPs. When the biomass/Pd (w/w) ratio increased to six or higher, Cr(VI) reduction achieved maximum rate that 50 mg/L of Cr(VI) could be rapidly reduced in one minute.

关键词： Palladium nanoparticles     Activated sludge     Hexavalent chromium    

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Relative expression of PTTG and bFGF in oral squamous cell carcinoma and Tca8113

Yumei DING BM , Lili CHEN MD , Bo CHENG PhD , Handong ZHANG MM ,

《医学前沿（英文）》 2009年 第3卷 第3期   页码 357-362 doi: 10.1007/s11684-009-0046-1

摘要： The purpose of this study was to investigate the expression of pituitary tumor transforming gene (PTTG) and basic fibroblast growth factor (bFGF) in oral squamous cell carcinoma (OSCC) and tongue cancer cell line Tca8113, as well as their effects on each other. We detected PTTG protein and bFGF in OSCC tissues from 56 cases using the streptavidin-biotin peroxidase (S-P) method; additionally, after being treated with different concentrations of anti bFGF or PTTG antibody, PTTG or bFGF expression in Tca8113 was examined by immunocytochemistry. The results were as follows: (1) Positive rates of PTTG protein and bFGF were 78.2% and 67.3% in OSCC, respectively, which were significantly higher than those in normal mucosal tissues (<0.05). PTTG protein was significantly up-regulated in poorly and moderately differentiated tumors compared to well differentiated tumors (<0.05), and there was also a significant difference between tumors with lymph node metastasis and tumors without lymph node metastasis (<0.05). PTTG protein expression was positively correlated with bFGF ( = 0.382, <0.05); (2) PTTG protein emitted strong fluorescence in Tca8113, and it decreased after being treated with anti-bFGF antibody. Anti-PTTG antibody also had an inhibitive effect on bFGF expression. In summary, the overexpression of PTTG protein is closely related with OSCC differentiation and lymph node metastasis. PTTG protein expression conforms to bFGF in OSCC tissues and Tca8113 cells. Detection of both PTTG and bFGF may help to judge the degree of malignancy and prognosis of patients with OSCC.

关键词： carcinoma     squamous cell     pituitary tumor transforming gene (PTTG) protein     basic fibroblast growth factor    

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Iteration framework for solving mixed lubrication computation problems

《机械工程前沿（英文）》 2021年 第16卷 第3期   页码 635-648 doi: 10.1007/s11465-021-0632-8

摘要： The general discrete scheme of time-varying Reynolds equation loses the information of the previous step, which makes it unreasonable. A discretization formula of the Reynolds equation, which is based on the Crank–Nicolson method, is proposed considering the physical message of the previous step. Gauss–Seidel relaxation and distribution relaxation are adopted for the linear operators of pressure during the numerical solution procedure. In addition to the convergent criteria of pressure distribution and load, an estimation framework is developed to investigate the relative error of the most important term in the Reynolds equation. Smooth surface with full contacts and mixed elastohydrodynamic lubrication is tested for validation. The asperity contact and sinusoidal wavy surface are examined by the proposed discrete scheme. Results show the precipitous decline in the boundary of the contact area. The relative error suggests that the pressure distribution is reliable and reflects the accuracy and effectiveness of the developed method.

关键词： mixed lubrication     discretization formula     relative error     Reynolds equation     asperity    

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大相对口径大线视场光学系统的设计

潘君骅

《中国工程科学》 2000年 第2卷 第8期   页码 89-90

摘要：

文章论述了用于红外远距离探测的光学应是全反射式的大相对口径、大视场的离轴非球面系统。给出了一个通光口径为Φ600mm，相对口径1:1.67，线视场为±5°的设计结果。

关键词： 红外探测     相对口径     大视场     离轴系统     非球面    

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FY-3B卫星微波湿度计热真空定标方法和结果分析

王振占,张升伟,李靖,李芸,吴琼

《中国工程科学》 2013年 第15卷 第10期   页码 33-46

摘要：

本文论述了风云三号卫星B星微波湿度计（MWHS-3B）发射前热真空定标的原理和方法，建立了各种定标误差的修正算法，获得了MWHS-3B的系统线性度、观测不同目标的灵敏度和最终定标精度等关键技术指标。这些参数已经用于MWHS-3B在轨数据的处理。

关键词： 风云三号卫星     微波湿度计     发射前定标     热真空定标    

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Analysis of stress and failure in rock specimens with closed and open flaws on the surface

《结构与土木工程前沿（英文）》 2021年 第15卷 第5期   页码 1222-1237 doi: 10.1007/s11709-021-0773-1

摘要： The influence of closed and open surface flaws on the stress distribution and failure in rock specimens is investigated. Heterogeneous finite element models are developed to simulate the compression tests on flawed rock specimens. The simulated specimens include those with closed flaws and those with open flaws on the surface. Systematic analyses are conducted to investigate the influences of the flaw inclination, friction coefficient and the confining stress on failure behavior. Numerical results show significant differences in the stress, displacement, and failure behavior of the closed and open flaws when they are subjected to pure compression; however, their behaviors under shear and tensile loads are similar. According to the results, when compression is the dominant mode of stress applied to the flaw surface, an open flaw may play a destressing role in the rock and relocate the stress concentration and failure zones. The presented results in this article suggest that failure at the rock surface may be managed in a favorable manner by fabricating open flaws on the rock surface. The insights gained from this research can be helpful in managing failure at the boundaries of rock structures.

关键词： surface flaw     heterogeneity     circular hole     numerical modeling     relative displacement    

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The preparation and performance of lignin-based activated carbon fiber adsorbents for treating gaseous streams

Min Song, Wei Zhang, Yongsheng Chen, Jinming Luo, John C. Crittenden

《化学科学与工程前沿（英文）》 2017年 第11卷 第3期   页码 328-337 doi: 10.1007/s11705-017-1646-y

摘要： Two types of lignin-based carbon fibers were prepared by electrospinning method. The first was activated with Fe O (LCF-Fe), and the second was not activated with Fe O (LCF). Gas phase adsorption isotherms for toluene on LCF-Fe and LCF were studied. The gas phase adsorption isotherm for 0% RH showed LCF-Fe have about 439 mg/g adsorption capacity which was close to that of commercially available activated carbon (500 mg/g). The Dubinin-Radushkevich equation described the isotherm data very well. Competitive adsorption isotherms between water vapor and toluene were measured for their RH from 0 to 80%. The effect of humidity on toluene gas-phase adsorption was predicted by using the Okazaki et al. model. In addition, a constant pattern homogeneous surface diffusion model (CPHSDM) was used to predict the toluene breakthrough curve of continuous flow-packed columns containing LCF-Fe, and its capacity was 412 mg/g. Our study, which included material characterization, adsorption isotherms, kinetics, the impact of humidity and fixed bed performance modeling, demonstrated the suitability of lignin-based carbon fiber for volatile organic compound removal from gas streams.

关键词： lignin     carbon fiber     electrospinning     toluene     humidity    

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Contact of surfaces and contact characteristics of offset surfaces

CAO Lixin, GONG Hu, LIU Jian

《机械工程前沿（英文）》 2008年 第3卷 第3期   页码 318-324 doi: 10.1007/s11465-008-0067-5

摘要： Based on differential geometry, the contact problems of two surfaces are discussed in this paper. The relationship between the contact status of two surfaces and that of offset surfaces are also analyzed. For a 5-axis NC machining, some research such as optimization of cutter location and calculation of the geometrical cusp height are important. The research results indicate that the relative normal curvature is an important geometrical invariant for describing the contact state of two surfaces. For point contact two surfaces, the calculation equation for the second order remained error is given. For line contact two surfaces, the condition of the second order line contact is that the principal directions and curvatures of the two surfaces are the same along the contact curve. If two surfaces keep the second order line contact, their two offset surfaces will also keep the second order line contact, and their third order remained errors are also uniform with that of the two offset surfaces.

关键词： relative     important geometrical     relationship     geometrical invariant     calculation    

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标题 作者 时间 类型 操作

Influence of environmental temperature and relative humidity on photocatalytic oxidation of toluene on

GUO Ting, BAI Zhipeng, WU Can, ZHU Tan

期刊论文

Modeling of coal swelling induced by water vapor adsorption

Zhejun PAN

期刊论文

Organic nitrogen in PM

Qian ZHANG,Fengkui DUAN,Kebin HE,Yongliang MA,Haiyan LI,Takashi KIMOTO,Aihua ZHENG

期刊论文

Abatement of mixed volatile organic compounds in a catalytic hybrid surface/packed-bed discharge plasma reactor

Lianjie Guo, Nan Jiang, Jie Li, Kefeng Shang, Na Lu, Yan Wu

期刊论文

EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

期刊论文

Measurement of bone alkaline phosphatase and relative study with osteosarcoma

YANG Zhiping, LI Jianmin, LI Xin, HUO Yanqing, SUN Guangzhi

期刊论文

Evaluation of the relative risk of stroke in patients with hypertension using cerebrovascular hemodynamic

HUANG Jiuyi, WANG Guiqing, GUO Jiping, CAO Yifeng, WANG Yan, YANG Yongju, YU Xuehai

期刊论文

palladium prepared by activated sludge microbes for the hexavalent chromium catalytic reduction: Impact of relative

Luman Zhou, Chengyang Wu, Yuwei Xie, Siqing Xia

期刊论文

Relative expression of PTTG and bFGF in oral squamous cell carcinoma and Tca8113

Yumei DING BM , Lili CHEN MD , Bo CHENG PhD , Handong ZHANG MM ,

期刊论文

Iteration framework for solving mixed lubrication computation problems

期刊论文

大相对口径大线视场光学系统的设计

潘君骅

期刊论文

FY-3B卫星微波湿度计热真空定标方法和结果分析

王振占,张升伟,李靖,李芸,吴琼

期刊论文

Analysis of stress and failure in rock specimens with closed and open flaws on the surface

期刊论文

The preparation and performance of lignin-based activated carbon fiber adsorbents for treating gaseous streams

Min Song, Wei Zhang, Yongsheng Chen, Jinming Luo, John C. Crittenden

期刊论文

Contact of surfaces and contact characteristics of offset surfaces

CAO Lixin, GONG Hu, LIU Jian

期刊论文