资源类型

期刊论文 143

会议视频 1

年份

2024 1

2023 15

2022 13

2021 17

2020 7

2019 7

2018 10

2017 7

2016 3

2015 6

2014 7

2013 5

2012 7

2011 5

2010 2

2009 7

2008 7

2007 8

2006 1

2005 2

展开 ︾

关键词

中子通量密度 2

功率密度 2

功率谱密度 2

8英寸 1

Au/Ti双功能催化剂 1

BNCT医院中子照射器 1

GPU;密度峰值;聚类;并行计算 1

H2有效利用率 1

Mie散射 1

三维守恒 1

不确定威胁 1

丙烯环氧化 1

中子和γ吸收剂量率 1

中子能谱 1

五脏功能 1

人群计数;密度估计;分割先验图;均匀函数 1

优快钻井 1

健康状态 1

养殖密度 1

展开 ︾

检索范围:

排序: 展示方式:

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    

Image analysis of soil failure on defective underground pipe due to cyclic water supply and drainage using X-ray CT

Toshifumi MUKUNOKI, Naoko KUMANO, Jun OTANI

《结构与土木工程前沿(英文)》 2012年 第6卷 第2期   页码 85-100 doi: 10.1007/s11709-012-0159-5

摘要: The ground subsidence on the underground pipe often is caused with the reduction of the effective stress and the loss of suction in the base course and then, soil drainage into the pipe. The final formation of the cavity growth in the ground was observed as the ground subsidence. Authors focused this problem and hence performed model tests with water-inflow and drainage cycle in the model ground. The mechanism of cavity generation in the model ground was observed using an X-ray Computed Tomography (CT) scanner. In those studies, water was supplied into the model grounds from the defected underground pipe model in case of the change of relative density and grain size distribution. As results, it was observed that the loosening area was generated from the defected part with water-inflow and some of the soil particles in the ground were drained into the underground pipe through the defected part. And afterward, the cavity was generated just above the defected part of the model pipe in the ground. Based on this observation, it might be said that the bulk density of soil around the defected pipe played one of key factor to generate the cavity in the ground. Moreover, the dimension of the defected part should be related to the magnification of the ground subsidence, in particular, crack width on a sewerage pipe and particle size would be the quantitative factor to evaluate the magnification of the ground subsidence. ?In this paper, it was concluded that the low relative density of soil would become the critical factor to cause the fatal failure of model ground if the maximum grain size was close to the dimension of crack width of defective part. The fatal collapse of the ground with high relative density more than 80% would be avoided in a few cycles of water inflow and soil drainage.

关键词: relative density     grain property     model test     road subsidence     underground pipe     image processing     X-ray CT    

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.

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    

Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1399-1

摘要:

• With the same charge, current density had little effect on As(III) removal in ACEC.

关键词: Electrocoagulation     Air cathode     Arsenic     Current density     Energy consumption    

Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

《医学前沿(英文)》 2009年 第3卷 第3期   页码 323-329 doi: 10.1007/s11684-009-0061-2

摘要: The purpose of this article is to determine the effect of a well-designed combined aerobic, resistance, and extension exercise program on bone mineral density (BMD) in postmenopausal women. The population comprised 45 postmenopausal women, who exercised over 12months (exercise group), and 36 women who served as a non-training control group. BMD of the hip, and lumbar spine was measured at the baseline and 12th month. Repeated measurement analysis of variance and nonparametric test were utilized to compare differences between the exercise group and controls. Thirty-six out of 45 persons in the exercise group and 36 controls completed the study. Average compliance was 82.2% for the whole exercise group at the 12th month. All the subjects had decreased BMD, but the rate of bone loss was lower in the exercise group than in the control group at the L4 and hip. Although the exercise program in this study may probably reduce the rate of bone loss in weight-bearing skeletal sites, we do not suggest the exercise by itself be viewed as prevention or treatment for osteoporosis. Further, the exact dose-response relationship of exercise and bone mass in early postmenopause is not clear.

关键词: early postmenopausal women     bone mineral density     exercise     effects    

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    

density measurement for plastic injection molding via ultrasonic technology

《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0714-2

摘要: Density variation during the injection molding process directly reflects the state of plastic melt and contains valuable information for process monitoring and optimization. Therefore, in-situ density measurement is of great interest and has significant application value. The existing methods, such as pressure−volume−temperature (PVT) method, have the shortages of time-delay and high cost of sensors. This study is the first to propose an in-situ density measurement method using ultrasonic technology. The analyses of the time-domain and frequency-domain signals are combined in the proposed method. The ultrasonic velocity is obtained from the time-domain signals, and the acoustic impedance is computed through a full-spectral analysis of the frequency-domain signals. Experiments with different process conditions are conducted, including different melt temperature, injection speed, material, and mold structure. Results show that the proposed method has good agreement with the PVT method. The proposed method has the advantages of in-situ measurement, non-destructive, high accuracy, low cost, and is of great application value for the injection molding industry.

关键词: ultrasonic measurement     melt density     in-situ measurement     injection molding    

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    

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    

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    

Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor

JIANG Yuan, TIAN Xuehong, YUAN Jie, JIN Yuemei, TAN Yusong

《医学前沿(英文)》 2007年 第1卷 第4期   页码 398-400 doi: 10.1007/s11684-007-0077-4

摘要: The aim of this paper was to investigate the relationship between the expression of adrenomedullin (ADM) and microvessel density (MVD) and prognosis in smooth muscle tumor of uterus. The expression of ADM was detected using immunohistochemical staining in specimens from 15 normal controls, 28 cases of uterine leiomyoma (LE) and 19 cases of uterine leiomyosarcoma (LES). The MVD was assayed by immunostainting with CD. There was a positive correlation between the ADM expression and MVD in LE and LES respectively ( = 0.823, <0.01; = 0.793, <0.01). The expression of ADM in LE was statistically lower than that in LES (<0.05). There was a positive correlation between the ADM expression and mitotic figures in LES (<0.05): the more mitotic figures, the higher levels of the ADM expression and poor prognosis. The ADM is an important angiogenic factor in smooth muscle tumor of uterus. The ADM can be used as an accessory marker in estimating the malignant potency of LE and judging the pro gnosis of LES, and as a novel molecular target of anti-angiogenic and anticarcinogenic strategies.

关键词: anticarcinogenic     microvessel density     malignant potency     muscle     uterine leiomyosarcoma    

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    

Single-electromagnet levitation for density measurement and defect detection

Yuhan JIA, Peng ZHAO, Jun XIE, Xuechun ZHANG, Hongwei ZHOU, Jianzhong FU

《机械工程前沿(英文)》 2021年 第16卷 第1期   页码 186-195 doi: 10.1007/s11465-020-0608-0

摘要: This paper presents a single-electromagnet levitation device to measure the densities and detect the internal defects of antimagnetic materials. The experimental device has an electromagnet in its lower part and a pure iron core in the upper part. When the electromagnet is activated, samples can be levitated stably in a paramagnetic solution. Compared with traditional magnetic levitation devices, the single-electromagnet levitation device is adjustable. Different currents, electromagnet shapes, and distances between the electromagnet and iron core are used in the experiment depending on the type of samples. The magnetic field formed by the electromagnet is strong. When the concentration of the MnCl aqueous solution is 3 mol/L, the measuring range of the single-electromagnet levitation device ranges from 1.301 to 2.308 g/cm . However, with the same concentration of MnCl aqueous solution (3 mol/L), the measuring range of a magnetic levitation device built with permanent magnets is only from 1.15 to 1.50 g/cm . The single-electromagnet levitation device has a large measuring range and can realize accurate density measurement and defect detection of high-density materials, such as glass and aluminum alloy.

关键词: single-electromagnet     electromagnetic levitation     density measurement     defect detection    

Application of gamma-ray attenuation technology in density measurement of a slurry reactor

Jian XU, Weisheng WEI, Kai ZHANG

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 486-490 doi: 10.1007/s11705-010-0509-6

摘要: Axial density profile of the gas-liquid-solid mixture in a slurry bubble column was measured by gamma-ray attenuation technology. Several measures for improving measurement precision were presented based on the discussion on attenuation law. It was found that the response frequency and the ray intensity should be as high as possible to improve the measurement precision. The mass absorption coefficient depended on not the object’s thickness but the location where the object was placed between the ray source and the detector. The results showed that the density in the column decreases with the increase of column height, which indicates that the measurement by gamma-ray attenuation is reasonable.

关键词: slurry reactor     axial density distribution     gamma-ray attenuation technology    

标题 作者 时间 类型 操作

EXPLORING THE RELATIVE ADVANTAGES OF LOCAL INNOVATION IN AGROFORESTRY

期刊论文

Image analysis of soil failure on defective underground pipe due to cyclic water supply and drainage using X-ray CT

Toshifumi MUKUNOKI, Naoko KUMANO, Jun OTANI

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

Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

期刊论文

Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

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

density measurement for plastic injection molding via ultrasonic technology

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

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

Relationship of adrenomedullin expression and microvessel density and prognosis in smooth muscle tumor

JIANG Yuan, TIAN Xuehong, YUAN Jie, JIN Yuemei, TAN Yusong

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

Single-electromagnet levitation for density measurement and defect detection

Yuhan JIA, Peng ZHAO, Jun XIE, Xuechun ZHANG, Hongwei ZHOU, Jianzhong FU

期刊论文

Application of gamma-ray attenuation technology in density measurement of a slurry reactor

Jian XU, Weisheng WEI, Kai ZHANG

期刊论文