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制干辣椒新品种石线4号的选育
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作者 宋文胜 李树贤 薛琳 《蔬菜》 2003年第7期13-13,共1页
关键词 制干辣椒 新品种 石线4号” 选育 特征特性 栽培技术
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兖石线混凝土轨枕裂损成因及防治对策
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作者 石兰平 《铁道技术监督》 1999年第12期18-20,共3页
关键词 石线 铁路 混凝土轨枕 裂损 成因 防治对策
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兖石线K169岩溶路基塌陷原因分析及整治 被引量:1
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作者 董森 《铁道勘察》 2011年第2期63-65,共3页
结合兖石线K169处岩溶路基塌陷工程实例,分析了岩溶路基塌陷原因。采用压力注浆方案对塌陷区域进行工程整治,重点介绍了压力注浆的工艺流程及质量控制方法。
关键词 石线 岩溶塌陷 压力注浆 质量控制
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Preoperative CT radiomics models for predicting composition of in vivo urinary calculi
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作者 TANG Lei WANG Shixia +3 位作者 LI Wuchao ZENG Xianchun AN Yunzhao SONG Bin 《中国医学影像技术》 CSCD 北大核心 2024年第8期1216-1220,共5页
Objective To observe the value of preoperative CT radiomics models for predicting composition of in vivo urinary calculi.Methods Totally 543 urolithiasis patients were retrospectively enrolled and divided into calcium... Objective To observe the value of preoperative CT radiomics models for predicting composition of in vivo urinary calculi.Methods Totally 543 urolithiasis patients were retrospectively enrolled and divided into calcium oxalate monohydrate stone group(group A,n=373),anhydrous uric acid stone group(group B,n=86),carbonate apatite group(group C,n=30),ammonium urate stone group(group D,n=28)and ammonium magnesium phosphate hexahydrate stone group(group E,n=26)according to the composition of calculi,also divided into training set and test set at the ratio of 7∶3.Radiomics features were extracted and screened based on plain CT images of urinary system.Five binary task models(model A—E corresponding to group A—E)and a quinary task model were constructed using least absolute shrinkage and selection operator algorithm for predicting the composition of calculi in vivo.Then receiver operating characteristic curves were drawn,and the area under the curves(AUC)were calculated to evaluate the predictive efficacy of binary task models,while the accuracy,precision,recall and F1 score were used to evaluate the predictive efficacy of the quinary task model.Results All binary task models had good efficacy for predicting the composition of urinary calculi in vivo,with AUC of 0.860—0.948 in training set and of 0.856—0.933 in test set.The accuracy,precision,recall and F1 score of the quinary task model for predicting the composition of in vivo urinary calculi was 82.25%,83.79%,46.23%and 0.596 in training set,respectively,while was 80.63%,75.26%,43.48%and 0.551 in test set,respectively.Conclusion Binary task radiomics models based on preoperative plain CT had good efficacy for predicting the composition of in vivo urinary calculi,while the quinary task radiomics model had high accuracy but relatively poor stability. 展开更多
关键词 UROLITHIASIS tomography X-ray computed radiomics
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Self-supervised learning artificial intelligence noise reduction technology based on the nearest adjacent layer in ultra-low dose CT of urinary calculi
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作者 ZHOU Cheng LIU Yang +4 位作者 QIU Yingwei HE Daijun YAN Yu LUO Min LEI Youyuan 《中国医学影像技术》 CSCD 北大核心 2024年第8期1249-1253,共5页
Objective To observe the value of self-supervised deep learning artificial intelligence(AI)noise reduction technology based on the nearest adjacent layer applicated in ultra-low dose CT(ULDCT)for urinary calculi.Metho... Objective To observe the value of self-supervised deep learning artificial intelligence(AI)noise reduction technology based on the nearest adjacent layer applicated in ultra-low dose CT(ULDCT)for urinary calculi.Methods Eighty-eight urinary calculi patients were prospectively enrolled.Low dose CT(LDCT)and ULDCT scanning were performed,and the effective dose(ED)of each scanning protocol were calculated.The patients were then randomly divided into training set(n=75)and test set(n=13),and a self-supervised deep learning AI noise reduction system based on the nearest adjacent layer constructed with ULDCT images in training set was used for reducing noise of ULDCT images in test set.In test set,the quality of ULDCT images before and after AI noise reduction were compared with LDCT images,i.e.Blind/Referenceless Image Spatial Quality Evaluator(BRISQUE)scores,image noise(SD ROI)and signal-to-noise ratio(SNR).Results The tube current,the volume CT dose index and the dose length product of abdominal ULDCT scanning protocol were all lower compared with those of LDCT scanning protocol(all P<0.05),with a decrease of ED for approximately 82.66%.For 13 patients with urinary calculi in test set,BRISQUE score showed that the quality level of ULDCT images before AI noise reduction reached 54.42%level but raised to 95.76%level of LDCT images after AI noise reduction.Both ULDCT images after AI noise reduction and LDCT images had lower SD ROI and higher SNR than ULDCT images before AI noise reduction(all adjusted P<0.05),whereas no significant difference was found between the former two(both adjusted P>0.05).Conclusion Self-supervised learning AI noise reduction technology based on the nearest adjacent layer could effectively reduce noise and improve image quality of urinary calculi ULDCT images,being conducive for clinical application of ULDCT. 展开更多
关键词 urinary calculi tomography X-ray computed artificial intelligence prospective studies
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中国第四纪晚更新世晚期以来冰缘环境 被引量:1
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作者 崔之久 宋长青 《地球科学进展》 CAS CSCD 1993年第2期1-8,共8页
本文根据古植被、古动物的间接标志以及冰缘现象等直接标志为依据,认为把我国晚更新世多年冻土南界划到北纬39—40°最为合适。进入全新世中国北方的气候出现过明显的波动和干湿变化,在高温期时气温较现在高1—2℃,在小冰期气温较... 本文根据古植被、古动物的间接标志以及冰缘现象等直接标志为依据,认为把我国晚更新世多年冻土南界划到北纬39—40°最为合适。进入全新世中国北方的气候出现过明显的波动和干湿变化,在高温期时气温较现在高1—2℃,在小冰期气温较现在低2.0—2.5℃。这些变化对植被和动物的生存、迁移以及人类活动产生深刻的影响。此外,多年冻土下限和雪线高度与现代相比有明显的变化。 展开更多
关键词 晚更新世 冰缘环境 石线 多年冻土 第四纪
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新疆主要制干辣椒品种及其适应性 被引量:4
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作者 宋文胜 王诚军 +1 位作者 李建华 贾红 《农村科技》 2003年第4期31-31,共1页
<正> 1、石线二号石河子蔬菜研究所选育,1982年9月通过自治区农作物品种审定委员会审定。石线二号属无限分枝类型,植株株型紧凑,分枝性能中等,株高50厘米左右,开展度25厘米左右,叶长卵圆形,叶色绿,第一花着生节位12~13节,果实单... <正> 1、石线二号石河子蔬菜研究所选育,1982年9月通过自治区农作物品种审定委员会审定。石线二号属无限分枝类型,植株株型紧凑,分枝性能中等,株高50厘米左右,开展度25厘米左右,叶长卵圆形,叶色绿,第一花着生节位12~13节,果实单生、双生或簇生,每簇1~3果,果实长14~15厘米,粗1.2厘米左右,长指形,果实顶部渐细尖,青果深绿色,单果重5克左右,干果大红色,无青尖现象,味辛辣,易制干,早熟,全生育期150天左右,对新疆气候适应性强,667米~2产250~300千克。目前生产上使用的石线二号品种为原石线一号和石线二号品种的混交后代,多由农民自己留种,品种性状差异很大,农民称之为'土种子'。该品种因早熟性好,对当地气候适应性好,在北疆地区仍有较大种植面积,但该品种无规范制种单位,种子质量不稳定,且抗病性较差,干椒果实色泽偏黄,应进行更新。 展开更多
关键词 新疆 辣椒 适应性 制干品种 石线二号品种 新椒四号四种 选育 特征特性
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Calculations of rock matrix modulus based on a linear regression relation 被引量:5
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作者 贺锡雷 贺振华 +2 位作者 汪瑞良 王绪本 蒋炼 《Applied Geophysics》 SCIE CSCD 2011年第3期155-162,239,共9页
The rock matrix bulk modulus or its inverse, the compressive coefficient, is an important input parameter for fluid substitution by the Biot-Gassmann equation in reservoir prediction. However, it is not easy to accura... The rock matrix bulk modulus or its inverse, the compressive coefficient, is an important input parameter for fluid substitution by the Biot-Gassmann equation in reservoir prediction. However, it is not easy to accurately estimate the bulk modulus by using conventional methods. In this paper, we present a new linear regression equation for calculating the parameter. In order to get this equation, we first derive a simplified Gassmann equation by using a reasonable assumption in which the compressive coefficient of the saturated pore fluid is much greater than the rock matrix, and, second, we use the Eshelby- Walsh relation to replace the equivalent modulus of a dry rock in the Gassmann equation. Results from the rock physics analysis of rock sample from a carbonate area show that rock matrix compressive coefficients calculated with water-saturated and dry rock samples using the linear regression method are very close (their error is less than 1%). This means the new method is accurate and reliable. 展开更多
关键词 Bulk modulus rock matrix fluid substitution rock physics linear regression
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Effects of sonic speed on location accuracy of acoustic emission source in rocks 被引量:12
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作者 李启月 董陇军 +2 位作者 李夕兵 殷志强 刘希灵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第12期2719-2726,共8页
To quantitatively study the location errors induced by deviation of sonic speed, the line and plane location tests were carried out. A broken pencil was simulated as acoustic emission source in the rocks. The line and... To quantitatively study the location errors induced by deviation of sonic speed, the line and plane location tests were carried out. A broken pencil was simulated as acoustic emission source in the rocks. The line and plane location tests were carried out in the granite rod using two sensors and the cube of marble using four sensors, respectively. To compare the position accuracy between line and plane positions, the line poison test was also carried out on the marble surface. The results show that for line positioning, the maximum error of absolute distance is about 0.8 cm. With the speed difference of 200 m/s, the average value of absolute difference from the position error is about 0.4 cm. For the plane positioning, in the case of the sensor array of 30 cm, the absolute positioning distance is up to 8.7 cm. It can be seen that the sonic speed seriously impacts on the plane positioning accuracy. The plane positioning error is lager than the line positioning error, which means that when the line position can satisfy the need in practical engineering, it is better to use the line position instead of the plane location. The plane positioning error with the diagonal speed is the minimum one. 展开更多
关键词 acoustic emission source sonic speed line location plane positioning ROCK
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Caustics study of the effect of glass fibres on dynamic fracture of hardened cement paste 被引量:1
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作者 杨立云 杨仁树 +1 位作者 赵雪楠 方士正 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期475-479,共5页
The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabric... The reflected optical caustics method is applied to study dynamic fracture problems in hardened cement paste. First both the unreinforced cement paste and the glass fibres reinforced cement paste specimens were fabricated and the reflective coating on the surface of the specimen was prepared. Secondly the crack path and the shadow spot patterns during the crack propagation process for the two specimens were recorded by using a multi-spark high speed camera.Thirdly some dynamic parameters of two cement paste specimens including crack onset time the dynamic stress intensity factor and crack growth velocity were determined and analyzed comparatively.This indicates that the glass fibres can improve the fracture resistance and delay fracture time.These results will play an important role in evaluating the dynamic fracture properties of cement paste. 展开更多
关键词 reflected optical caustics cement paste glass FIBRE dynamic fracture dynamic stress intensity factor reflected optical caustics cement paste glass FIBRE dynamic fracture dynamic stress intensity factor
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Self-heating tendency evaluation of sulfide ores based on nonlinear multi-parameters fusion 被引量:1
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作者 潘伟 吴超 +1 位作者 李孜军 杨月平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第2期582-589,共8页
In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials ... In order to reveal the nonlinear dynamics characteristics of unsteady self-heating process of sulfide ores, nine different kinds of sulfide ore samples from a pyrite mine in China were taken as experimental materials and their self-heating characteristics were measured in laboratory. Furthermore, the measured temperature was studied by integrating wavelet transform, nonlinear characteristic parameters extraction and fuzzy comprehensive evaluation. The results indicate that only the ore samples 1, 2, 6 and 9 have obvious self-heating phenomenon, and their self-heating initiative temperatures are 220 ℃, 239 ℃, 220 ℃ and 220 ℃, respectively, which means that they are difficult to produce self-heating under normal mining conditions. The correlation dimension of self-heating process is fraction and the maximum Lyapunov exponent is positive, which means that it is feasible to study the self-heating process based on chaotic dynamics theory. The nonlinearities of self-heating process of these four samples (ore samples 1, 2, 6 and 9) are 0.8227, 0.7521, 0.9401 and 0.8827 respectively and the order of the samples according to these results is: sample 6, sample 9, sample 1, sample 2, which is consistent with the measured results of self-heating characteristics. Therefore, the nonlinearity method can be used to evaluate the self-heating tendency of sulfide ores, and it is an effective verification of the reliability of measured results. 展开更多
关键词 sulfide ores self-heating process nonlinear characteristic parameter NONLINEARITY self-heating tendency
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电动转辙机在线动态测试
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作者 王岩 朱彬青 翟晓萍 《中国铁路》 1992年第12期32-33,共2页
目前我国铁路使用当中的电动转辙机,对其各项测试指标,特别是拉力尚无行之有效的测试方法,因此我们研制了一种用单片机控制的电动转辙机在线动态测试仪,该仪器可对使用当中的 ZD_6、ZD_7型电动转辙机进行动作电压、电流、时间、拉力和... 目前我国铁路使用当中的电动转辙机,对其各项测试指标,特别是拉力尚无行之有效的测试方法,因此我们研制了一种用单片机控制的电动转辙机在线动态测试仪,该仪器可对使用当中的 ZD_6、ZD_7型电动转辙机进行动作电压、电流、时间、拉力和摩擦电流的测试,测试结果用 CTD-1A 型打印绘图机以曲线方式打印输出,也可以不用打印机而用显示器直接读出,测试过程不影响电动转辙机的正常工作,最多可同时测14组,打印格式如图1。 展开更多
关键词 转辙器 石线动态测试 铁路
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正在崛起的现代化港城——山东省日照开发区招商引资促开发
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作者 周永泉 孙晓艳 《中外房地产导报》 1995年第8期34-35,共2页
日照是在改革开放中崛起的年轻新兴港口城市,位于中国东部沿海中段,山东半岛南翼,处于环黄海经济圈。东临荑海,西靠沂蒙山,背倚九州,南北各与连云港、青岛毗邻,隔海与日本、韩国、朝鲜相望。陆上经日照港至兖石线与全国铁路网相连,公路... 日照是在改革开放中崛起的年轻新兴港口城市,位于中国东部沿海中段,山东半岛南翼,处于环黄海经济圈。东临荑海,西靠沂蒙山,背倚九州,南北各与连云港、青岛毗邻,隔海与日本、韩国、朝鲜相望。陆上经日照港至兖石线与全国铁路网相连,公路经3条干线通往全国,海路直通中国沿海各港与五大洲30多个国家和地区通航。 日照是我国沿海开放城市之一。日照市下辖二区两县(日照开发区、东港区、五莲县、莒县)。 展开更多
关键词 日照开发区 日照市 招商引资 日照港 平方 中国沿海 黄海 石线 现代化 五莲县
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Optimization of Chromatographic Conditions for Detecting Ellagic Acid in Pomegranate Peels Using HPLC Method 被引量:3
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作者 夏小龙 彭蓉 +3 位作者 李树垠 李端阳 干霞 白琦 《Agricultural Science & Technology》 CAS 2012年第11期2400-2403,共4页
[Objective] This study aimed to optimize the chromatographic conditions for detecting ellagic acid in pomegranate peels using HPLC method. [Method] By using 0.2 mg/ml ellagic acid standard solution, on the basis of si... [Objective] This study aimed to optimize the chromatographic conditions for detecting ellagic acid in pomegranate peels using HPLC method. [Method] By using 0.2 mg/ml ellagic acid standard solution, on the basis of single-factor experiment and orthogonal experiment, chromatographic conditions (mobile phase ratio, flow rate, col- umn temperature) for detecting ellagic acid using HPLC were optimized. Based on the optimal chromatographic conditions, the ellagic acid content in experimental pomegranate peels was determined. [Resull] The optimal chromatographic conditions for detecting ellagic acid in pomegranate peels using HPLC method are: 1.2% phos- phoric acid:acetonitrile=85:15, column temperature of 35 ℃, and flow rate of 1.0 ml/min. The linear regression equation of ellagic acid is: y=2.9e+0.6x+4.4e+5 (FF=9 999). Ac- cording to the standard addition recovery test, the average recovery rate of ellagic acid is 98.20%, and RSD is 0.60%. Under above optimized chromatographic condi- tions, ellagic acid can be well separated from other interfering components in pomegranate peels, with shorter peak time and ideal effect, which is convenient for the detection in production practices. [Conclusion] This study laid the foundation for detecting ellagic acid in pomegranate peels using HPLC method. 展开更多
关键词 Pomegranate peel Etlagic acid DETECTION HPLC
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Computed tomographic differentiation between alcoholic and gallstone pancreatitis:Significance of distribution of infiltration or fluid collection 被引量:11
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作者 Young-Sun Kim Yongsoo Kim +1 位作者 Sung-Kyu Kim Hyunchul Rhim 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4524-4528,共5页
AIM: To evaluate the usefulness of various computed tomography (CT) findings including distribution of infiltration or fluid collection in differentiating the major etiologies of acute pancreatitis. METHODS: We re... AIM: To evaluate the usefulness of various computed tomography (CT) findings including distribution of infiltration or fluid collection in differentiating the major etiologies of acute pancreatitis. METHODS: We reviewed 75 relatively severe cases of acute pancreatitis of alcoholic (n = 43) or biliary stone (n = 32) etiology having infiltration or fluid collection on CT. We compared the pancreatic size, CT grading, presence or absence of biliary calculi, and dilatation of pancreatic or bile duct. We also evaluated degree and the distribution of infiltration and fluid collection in each group. RESULTS: The sizes of pancreas were not different between alcohol group and stone group. Alcohol group showed higher CT grading than stone group (P 〈 0.05). Presence of biliary stone and duct dilatation was statistically significant in differentiating etiology (P 〈 0.05). Alcohol group showed significantly prominent peripancreatic pathology than stone group only in left peritoneal compartment (P = 0.020). CONCLUSION: Alcoholic pancreatitis tends to form more prominent peripancreatic changes than gallstone pancreatitis in relatively severe cases. This is evident on the anterior aspect of left abdomen. Although clinical history and some CT findings usually are a major determinant of the etiology, this pattern of peripancreatic pathology may have an ancillary role in determining the etiologies of acute pancreatitis in the equivocal cases. 展开更多
关键词 PANCREATITIS PANCREAS Computed tomography PERITONEUM FLUID Retroperitoneal space
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Determination of chemical composition of gall bladder stones:Basis for treatment strategies in patients from Yaounde,Cameroon 被引量:2
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作者 FruF.AngwafoIII Samuel Takongmo Donald Griffith 《World Journal of Gastroenterology》 SCIE CAS CSCD 2004年第2期303-305,共3页
AIM:Gallstone disease is increasing in sub-saharan Africa (SSA).In the west, the majority of stones can be dissolved with bile salts,since the major component is cholesterol.This medical therapy is expensive and not r... AIM:Gallstone disease is increasing in sub-saharan Africa (SSA).In the west, the majority of stones can be dissolved with bile salts,since the major component is cholesterol.This medical therapy is expensive and not readily accessible to poor populations of SSA.It was therefore necessary to analyze the chemical composition of biliary stones in a group of patients,so as to make the case for introducing bile salt therapy in SSA.METHODS: All patients with symptomatic gallstones were recruited in the study. All stones removed during cholecystectomy were sent to Houston for x-ray diffraction analysis.Data on age, sex, serum cholesterol,and thepercentage by weight of cholesterol, calcium carbonate, and amorphous material in each stone was entered into a preestablished proforma. Frequencies of the major components of the stones were determined.RESULTS:Sixteen women and ten men aged between 27 and 73 (mean 44.9) years provided stones for the study.The majority of patients (65.38%) had stones with less than 25% of cholesterol.Amorphous material made up more than 50% and 100% of stones from 16 (61.53%) and 9 (34.61%) patients respectively.CONCLUSION:Cholesterol is present in small amounts in a minority of gallstones in Yaounde. Dissolution of gallstones with bile salts is unlikely to be successful. 展开更多
关键词 ADULT Aged Bile Acids and Salts Calcium Carbonate Cameroon CHOLESTEROL Cross-Sectional Studies Female GALLSTONES Humans Male Middle Aged Pilot Projects PREVALENCE
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Ordovician limestone aquosity prediction using nonlinear seismic attributes:Case from the Xutuan coal mine
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作者 黄亚平 董守华 耿建华 《Applied Geophysics》 SCIE CSCD 2009年第4期359-366,394,395,共10页
Ordovician limestone water is coal mines. In this paper, we analyze the the main source of water inrush in North China characteristic of three kinds of nonlinear seismic attributes, such as the largest lyapunov expone... Ordovician limestone water is coal mines. In this paper, we analyze the the main source of water inrush in North China characteristic of three kinds of nonlinear seismic attributes, such as the largest lyapunov exponent,fractal dimension and entropy and introduce their calculation methods. Taking the 81st and 82nd coal districts in the Xutuan coal mine as examples, we extract the three seismic attributes based on the 3D prestack migration seismic data of this area, which can display the Ordovician limestone fracture distribution in the mine. We comprehensively analyzed the three nonlinear seismic attributes and compared the results with transient electromagnetic exploration results and determined the possible Ordovician limestone aquosity distribution. This demonstrated that the nonlinear seismic attributes technology is an effective approach to predict the aquosity of Ordovician limestone. 展开更多
关键词 nonlinear seismic attribute LIMESTONE aquosity PREDICTION
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Gravel Accumulation in Deposits of Viscous Debris Flows with Hyper-concentration 被引量:2
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作者 WANG Yuyi TAN Rongzhi +1 位作者 JAN Chyandeng TIAN Bing 《Journal of Mountain Science》 SCIE CSCD 2009年第1期88-95,共8页
According to the observational data of viscous debris flows with hyper-concentration, debris flows can be classified into three types:high-viscous, viscous, and sub-viscous debris flows.Distinct formation mechanism of... According to the observational data of viscous debris flows with hyper-concentration, debris flows can be classified into three types:high-viscous, viscous, and sub-viscous debris flows.Distinct formation mechanism of different graded bedding structures in deposits of viscous debris flows was analyzed in this paper by using their yield-stress ratio and flow plug ratio.This paper specially analyzed the effect of Weissenberg which the gravels in squirm condition of hyper-concentration viscous flows would tend to move vertically, and the formation mechanism of the gravels accumulated at surface was also studied.The analysis in this paper can establish a foundation for the studies on differentiation of bedding structures of debris flow deposits and studies on dynamic parameters of debris flows. 展开更多
关键词 Viscous debris flow effective yield-stressratio flow plug ratio effect of Weissenberg gravelaccumulation at surface
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CifNet Network Multi-Well Data Management System 被引量:11
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作者 LiNing Mingchao CuiJian WangJianqiang WangCaizhi 《Applied Geophysics》 SCIE CSCD 2004年第2期129-131,共3页
The CifNet network multi-well data management system is developed for 100MB or 1000MB local network environments which are used in Chinese oil industry. The kernel techniques of CifNet system include: 1, establishing ... The CifNet network multi-well data management system is developed for 100MB or 1000MB local network environments which are used in Chinese oil industry. The kernel techniques of CifNet system include: 1, establishing a high efficient and low cost network multi-well data management architecture based on the General Logging Curve Theory and the Cif data format; 2, implementing efficient visit and transmission of multi-well data in C/S local network based on TCP/IP protocol; 3,ensuring the safety of multi-well data in store, visit and application based on Unix operating system security. By using CifNet system, the researcher in office or at home can visit curves of any borehole in any working area of any oilfield. The application foreground of CifNet system is also commented. 展开更多
关键词 MULTI-WELL NETWORK data management CifNet
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Catalytic Performance of Carbon Materials Supported Pd Nanoparticles in Selective Hydrogenation of Acetylene 被引量:2
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作者 姚繁繁 霍羽佳 马运生 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第5期559-565,I0002,共8页
Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization met... Pd/C catalysts were prepared by deposited Pd nanoparticles (NPs) on different carbon supports including activated carbon (AC), graphite oxide (GO), and reduced graphite oxide (rGO) using sol-immobilization method. Through transmission electron microscopy, powder X-ray di raction, and X-ray photoelectron spectroscopy, the role of the carbon supports for the catalytic performances of Pd/C catalysts was examined in selective hydrogenation of acetylene. The results indicate that Pd/AC exhibited higher activity and selectivity than Pd/GO and Pd/rGO in the gas phase selective hydrogenation of acetylene. Thermal and chemical treatment of AC supports also have some effect on the catalytic performance of Pd/AC catalysts. The differences in the activity and selectivity of various Pd/C catalysts were partly attributed to the metal-support interaction. 展开更多
关键词 Selective hydrogenation of acetylene Pd Active carbon Graphite oxide Reduced graphite oxide X-ray photoelectron spectroscopy
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