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Effects of the Water-Cement Ratio and the Molding Temperature on the Hydration Heat of Cement
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作者 代金鹏 HE Jie +1 位作者 WANG Qicai LOU Xuyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期990-998,共9页
The effects of the water-cement ratio and the molding temperature on the hydration heat of cement were investigated with semi-adiabatic calorimetry.The specimens were prepared with water-cement ratios of 0.31,0.38,and... The effects of the water-cement ratio and the molding temperature on the hydration heat of cement were investigated with semi-adiabatic calorimetry.The specimens were prepared with water-cement ratios of 0.31,0.38,and 0.45,and the molding temperature was specified at 10 and 20℃.The experimental results show that,as the water-binder ratio increases,the value of the second temperature peak on the temperature curve of the cement paste decreases,and the age at which the peak appears is delayed.The higher the water-cement ratio,the higher the hydration heat release in the early period of cement hydration,but this trend reverses in the late period.There are intersection points of the total hydration heat curve of the cement pastes under the influence of the water-cement ratio,and this law can be observed at both molding temperatures.With the increase in the molding temperature,the age of the second temperature peak on the temperature curve of the cement paste will advance,but the temperature peak will decrease.The higher the molding temperature,the earlier the acceleration period of the cement hydration began,and the larger the hydration heat of the cement in the early stage,but the smaller the total heat in the late period.A subsection function calculation model of the hydration heat,which was based on the existing models,was proposed in order to predict the heat of the hydration of the concrete. 展开更多
关键词 semi-adiabatic calorimetry hydration heat water-cement ratio molding temperature MODELING
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Crystallization Temperature and Crystallization Ratio of Mold Flux 被引量:8
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作者 ZHU Chuan-yun HAN Wen-dian +1 位作者 LIU Cheng-jun JIANG Mao-fa 《Journal of Iron and Steel Research International》 SCIE CAS CSCD 2005年第6期23-26,共4页
The factors influencing the crystallization ratio of mold flux were researched by rapid cooling technolo gy, and the factors affecting crystallization temperature were studied by single thermocouple technique. The res... The factors influencing the crystallization ratio of mold flux were researched by rapid cooling technolo gy, and the factors affecting crystallization temperature were studied by single thermocouple technique. The results showed that the crystallization ratio of mold flux increases with the basicity and the content of Na2O, CaF2, Li2O and NaF, and decreases with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. However, the crystallization temperature of mold flux rises with the basicity and the content of NaF, Na2O and CaF2, and reduces with the increase of the content of Al2O3, MgO, BaO, MnO and B2O3. But for Li2O, crystallization temperature decreases firstly to a minimum value at 2%, and then increases gradually with the increase of Li2O. 展开更多
关键词 mold flux crystallization temperature crystallization ratio VISCOSITY solidification temperature
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Combined preoperative platelet-to-lymphocyte ratio and serum carbohydrate antigen 19–9 level as a prognostic factor in patients with resected pancreatic cancer 被引量:4
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作者 Teruhisa Sakamoto Hiroaki Saito +3 位作者 Masataka Amisaki Naruo Tokuyasu Soichiro Honjo Yoshiyuki Fujiwara 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2019年第3期278-284,共7页
Background: Carbohydrate antigen 19–9(CA19-9) is the most frequently used tumor marker and serves as a prognostic indicator in patients with pancreatic cancer(PC). The platelet-to-lymphocyte ratio(PLR) is thought to ... Background: Carbohydrate antigen 19–9(CA19-9) is the most frequently used tumor marker and serves as a prognostic indicator in patients with pancreatic cancer(PC). The platelet-to-lymphocyte ratio(PLR) is thought to be an inflammation-related serum marker. An elevated PLR represents increased inflammatory status and is associated with poor prognosis in patients with various cancers including PC. Methods: This study involved 103 patients with a histopathological diagnosis of pancreatic ductal adenocarcinoma who underwent pancreatectomy. The patients were assessed to determine the prognostic significance of the combination of the PLR and CA19-9 level. Results: Based on the receiver operating characteristic analysis results, the patients were divided into PLR H igh(PLR ≥ 129.1) andPLRLow(PLR < 129.1) groups and into CA19-9High(CA19-9 ≥ 74.0 U/mL) and CA19-9Low(CA19-9 < 74.0 U/mL) groups. The cumulative 5-year overall survival(OS) and disease-specific survival(DSS) rates significantly differed by both the PLR(PLR H igh group: 19.5% and 22.9%;PLRLow group: 39.1% and 45.9%) and CA19-9(CA19-9 H igh group: 19.1% and 25.6%;CA19-9Low group: 41.0% and 41.0%). We then divided the patients into Groups A(PLR L ow/CA19-9Low), B(PLR Low/CA19-9High or PLRHigh/CA19-9Low), and C(PLR H igh/CA19-9High). The cumulative 5-year OS rates in Groups A, B, and C were 44.0%, 31.9%, and 11.9%, respectively( P = 0.002). The cumulative 5-year DSS rates in Groups A, B, and C were 47.7%, 36.4%, and 16.8%, respectively( P = 0.002). Multivariate analysis revealed that the combination of the PLR and CA19-9 was an independent prognostic factor in patients with resected PC. Conclusions: The combination of the PLR and CA19-9 is useful for predicting the prognosis of patients with resected PC. 展开更多
关键词 CA19-9 PANCREATIC cancer Platelet-to-lymphocyte ratio Prognosis
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Lymph node ratio and preoperative CA 19-9 levels predict overall survival and recurrence-free survival in patients with resected pancreatic adenocarcinoma 被引量:4
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作者 Sabrina C Wentz Zhi-Guo Zhao +5 位作者 Yu Shyr Chan-Juan Shi Kay Washington Nipun B Merchant Fen Xia A Bapsi Chakravarthy 《World Journal of Gastrointestinal Oncology》 SCIE CAS 2012年第10期207-215,共9页
AIM:Clinicopathologic factors predicting overall survival (OS) would help identify a subset to benefit from adjuvant therapy. METHODS: One hundred and sixty-nine patients patients from 1984 to 2009 with curative resec... AIM:Clinicopathologic factors predicting overall survival (OS) would help identify a subset to benefit from adjuvant therapy. METHODS: One hundred and sixty-nine patients patients from 1984 to 2009 with curative resections for pancreatic adenocarcinoma were included. Tumors were staged by American Joint Committee on Cancer 7th edition criteria. Univariate and multivariable analyses were performed using Kaplan-Meier methodology or Cox proportional hazard models. Log-rank tests were performed. Statistical inferences were assessed by two-sided 5% significance level. RESULTS: Median age was 67.1 (57.2-73.0) years with equal gender distribution. Tumors were in the head (89.3%) or body/tail (10.7%). On univariate analysis, adjuvant therapy, lymph node (LN) ratio, histologic grade, negative margin status, absence of peripancreatic extension, and T stage were associated with improved OS. Adjuvant therapy, LN ratio, histologic grade, number of nodes examined, negative LN status, and absence of peripancreatic extension were associated with improved recurrence-free survival (RFS). On multivariable analysis, LN ratio and carbohydrate antigen (CA) 19-9 levels were associated with OS. LN ratio was associated with RFS. CONCLUSION: The LN ratio and CA 19-9 levels are independent prognostic factors following curative resections of pancreatic cancer. 展开更多
关键词 Pancreatic ADENOCARCINOMA LYMPH node ratio CARBOHYDRATE ANTIGEN 19-9 Recurrence-free SURVIVAL Overall SURVIVAL
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Effect of Run - in Ratios on the Mechanical Properties of Two - Guide Bars Warp - Knitted Fabrics 被引量:1
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作者 陈雨梁 《Journal of China Textile University(English Edition)》 EI CAS 2000年第3期87-89,共3页
Warp knitting technology gets rapid development at present and becomes one of the most important parts of the textiles.But it is less known how the parameters of warp knitting technology affect the mechanical properti... Warp knitting technology gets rapid development at present and becomes one of the most important parts of the textiles.But it is less known how the parameters of warp knitting technology affect the mechanical properties of warp-knitted fabrics.This paper presents discuss a research on the relationships between run-in ratio and mechanical properties of the two-bar warp-knittedfabrics through the measurement and analysis of the mechanical properties of various samples with different run-in ratios.The optimal run一in ratios for the reasonable mechanical properties are obtained from above dis- 展开更多
关键词 RUN - in ratios MECHANICAL property TWO - bar WARP - KNITTED fabric .
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Change of Ecological Characteristics Due to Decrease of COD/SO_4^(2-) Ratio During Sulfate-reduction 被引量:2
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作者 王爱杰 任南琪 +1 位作者 刘广民 杜大仲 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2004年第2期151-155,共5页
In order to investigate the change of ecological characteristics due to the decrease of COD/SO_4^(2-) ratio during sulfate reduction, continuous-flew tests were conducted in an acidogenic sulfate-reducing reactor with... In order to investigate the change of ecological characteristics due to the decrease of COD/SO_4^(2-) ratio during sulfate reduction, continuous-flew tests were conducted in an acidogenic sulfate-reducing reactor with molasses wastewater as sole organic carbon source and sodium snlfate as electron acceptor, and the change of pH value, oxidation reduction potential (ORP), volatile fat acids (VFAs), alkalinity (ALK) and the predominant populations with COD/SO_4^(2-) ratio decreasing from 4.2 to 2.0 were investigated. The experimental results demonstrated that, with decreasing COD/SO_4^(2-) ratio, ORP and ALK increased, pH value decreased, and the proportion of acetic acid in terminal products decreased significantly, and a stable -type microbial community with high COD/SO_4^(2-) ratio was converted into a sub -stable -type one with low COD/SO_4^(2-) ratio. 展开更多
关键词 sulfate-reduction COD/SO_4^(2-)ratio ecological characteristic wastewater treatment
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Neutrophil-to-lymphocyte ratio and carbohydrate antigen 19-9 as prognostic markers for advanced pancreatic cancer patients receiving first-line chemotherapy 被引量:1
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作者 Kabsoo Shin Eun-Kyo Jung +3 位作者 Se Jun Park Sangwoon Jeong In-Ho Kim Myung-ah Lee 《World Journal of Gastrointestinal Oncology》 SCIE 2021年第8期915-928,共14页
BACKGROUND A decline in serum carbohydrate antigen 19-9(CA19-9)levels during systemic chemotherapy is considered as a prognostic marker for patients with advanced pancreatic cancer.Neutrophil-to-lymphocyte ratio(NLR)h... BACKGROUND A decline in serum carbohydrate antigen 19-9(CA19-9)levels during systemic chemotherapy is considered as a prognostic marker for patients with advanced pancreatic cancer.Neutrophil-to-lymphocyte ratio(NLR)has been extensively studied as a simple and useful indicator of prognosis in various cancers including pancreatic cancer.AIM To assess the prognostic significance of NLR and CA19-9 in patients with advanced pancreatic adenocarcinoma received first-line chemotherapy according to CA19-9 positivity.METHODS We retrospectively analyzed patients diagnosed with advanced pancreatic cancer who received first-line chemotherapy between January 2010 and July 2017 at the Catholic University of Seoul St.Mary’s Hospital.Patients were divided according to CA19-9 positivity(CA19-9-positive vs-negative groups)and pre-and posttreatment NLR levels.To determine cut-off value of NLR and CA19-9 reduction,time-dependent receiver operating characteristic curve was applied.We evaluated overall survival(OS)and progression-free survival(PFS)for each group using Kaplan-Meier method,and we performed multivariate analyses on the entire cohort.RESULTS We included 271 patients in this study.Cut-off value of NLR and CA19-9 reduction was determined as 2.62 and 18%.Multivariate analysis showed that post-treatment NLR<2.62 and reduction of≥18%of baseline CA19-9 were significantly associated with OS and PFS.Post-treatment NLR≥2.62 showed hazard ratio(HR)of 2.47[95%confidence interval(CI):1.84-3.32,P<0.001]and CA19-9 decline(≥18%)showed HR of 0.51(95%CI:0.39-0.67,P<0.001)for OS.When CA19-9-positive patients were divided into groups according to CA19-9 response(responder vs non-responder)and post-treatment NLR(<2.62 vs≥2.62),CA19-9 responder and post-treatment NLR<2.62 group showed better survival than CA19-9 non-responder and post-treatment NLR≥2.62 group(OS 11.0 mo vs 3.9 mo,P<0.001;PFS 6.3 mo vs 2.0 mo,P<0.001).The combination of CA19-9 decline and post-treatment NLR showed a significant correlation with clinical response in CA 19-9 positive group.Within the CA19-9-negative group,the posttreatment NLR<2.62 group showed better survival than the post-treatment NLR≥2.62 group(OS 12.7 mo vs 7.7 mo,P<0.001;PFS 6.7 mo vs 2.1 mo,P<0.001),and post-treatment NLR showed correlation with clinical response.CONCLUSION In advanced pancreatic cancer patients positive for CA19-9 and treated with systemic chemotherapy,the combination of post-treatment NLR<2.62 and 18%decline of CA19-9 at the first response evaluation is a good prognostic marker.Post-treatment NLR<2.62 alone could be used as a prognostic marker and an adjunctive tool for response evaluation in CA19-9-negative patients. 展开更多
关键词 Pancreatic adenocarcinoma Serum carbohydrate antigen 19-9 Neutrophil-tolymphocyte ratio Multivariate analysis PROGNOSIS CHEMOTHERAPY
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Tuning the particle size,physical properties,and photocatalytic activity of Ag_(3)PO_(4)materials by changing the Ag^(+)/PO_(4)^(3-)ratio 被引量:1
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作者 Hung N M Oanh L T M +4 位作者 Chung D P Thang D V Mai V T Hang L T Minh N V 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期561-568,共8页
This study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocataly... This study demonstrates the influence of the Ag^(+)/PO_(4)^(3-)ratio in precursor solution on the crystal structural formation,morphology,physical properties,and photocatalytic performance of a Ag_(3)PO_(4)photocatalyst that is fabricated,using a facile precipitation method,from AgNO_(3)and Na2HPO_(4)·12H_(2)O.The material characterizations were carried out using x-ray diffraction(XRD),scanning electron microscopy(SEM),energy-dispersive x-ray spectroscopy(EDX),Brunauer–Emmett–Teller(BET)surface area,Fourier transform infrared(FTIR)absorption,Raman scattering,x-ray photoelectron spectroscopy(XPS),UV-vis absorption,and photoluminescence(PL).The results show that Ag_(3)PO_(4)crystallizes better when the excess PO_(4)^(3-)content increases,and the lattice parameters decrease slightly,while the crystal diameter and the particle size increase.This change is also observed in the Raman scattering and FTIR spectra with the increase in the vibration frequency of the[PO_(4)]group.The compression of the[PO_(4)]unit was also confirmed in the XPS spectra with the shift of P 2p peaks toward higher binding energy.The photocatalytic results showed that the samples synthesized from excess PO_(4)^(3-)solution exhibited higher photocatalytic performance compared to the sample with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.A sample prepared from the precursor solution with a Ag^(+)/PO_(4)^(3-)ratio of 3:1.5 was optimal for RhB decomposition under both visible light and natural sunlight,completely decomposing 10 ppm RhB after 15 minutes of xenon lamp irradiation and after 60 minutes under solar light irradiation.This is attributed to the high crystallinity,small particle size and low electron–hole recombination rate of the sample. 展开更多
关键词 morphology PHOTOCATALYTIC Ag^(+)/PO_(4)^(3-)ratio visible light
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Mn/Fe比对Al-Mg-Si合金组织和性能的影响
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作者 刘雅婷 李元东 +3 位作者 刘文憬 王梓臣 罗晓梅 毕广利 《铸造》 CAS 2024年第5期587-595,共9页
以Al-Mg-Si合金为研究对象,采用金属型铸造研究Mn/Fe比对其组织和性能的影响。结果表明:Al-Mg-Si铸态合金组织中枝晶间存在α-Al基体和大量析出相,主要以Mg_(2)Si相为主,还存在少量的共晶Si相、AlFeSi相和Al(FeMn)Si相。随Mn/Fe比的增大... 以Al-Mg-Si合金为研究对象,采用金属型铸造研究Mn/Fe比对其组织和性能的影响。结果表明:Al-Mg-Si铸态合金组织中枝晶间存在α-Al基体和大量析出相,主要以Mg_(2)Si相为主,还存在少量的共晶Si相、AlFeSi相和Al(FeMn)Si相。随Mn/Fe比的增大,合金中的晶粒逐渐变得细小圆整,且由树枝晶向等轴晶发生转变。Mn可以促进铝合金中针状的β-AlFeSi相向骨骼状、颗粒状或块状的α-Al(FeMn)Si相的转变。当Mn/Fe比为0.5时,合金的热导率达到最大值181.08 W·m^(-1)·K^(-1)。当Mn/Fe比为1.0时,合金的晶粒尺寸最小且具有最佳的力学性能,抗拉强度、伸长率和硬度相较于Mn/Fe为0.2时分别提升17.45%、49.57%和27.48%,达到167.35 MPa、17.23%、HV 62.86。 展开更多
关键词 AL-MG-SI合金 Mn/Fe比 金属型铸造 力学性能 热导率
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Effects of Different NH_4^+/NO_3^- Ratio and Water Condition on Physiological Characteristics of Rice Seedlings
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作者 Haimei WU Xiaoyuan CHEN +1 位作者 Yupeng ZHANG Fujie WU 《Agricultural Science & Technology》 CAS 2017年第10期1908-1911,1924,共5页
[Objective] This study aimed to further explore the dynamics of related physiological indexes of rice seedlings under different NH4+ /NO3- ratio and different water condition. [Method] Under the hydroponic condition ... [Objective] This study aimed to further explore the dynamics of related physiological indexes of rice seedlings under different NH4+ /NO3- ratio and different water condition. [Method] Under the hydroponic condition in laboratory, 3 NH4+/NO3- ratios (0/100, 50/50 and 100/0) and 2 water conditions (+PEG,-PEG) were designed for Fengliangyou 7203. [Result] The root-canopy ratio of rice seedlings increased under any of the NH4+/NO3- ratios and water conditions. Under water stress, the root-canopy ratio of rice seedlings changed most greatly at the NH4+/NO3- ratio of 0/ 100; the overall water potential of rice seedlings reached the lowest at the NH4+/ NO3- ratio of 100/0; and the changes of water potential and xylem flow pH were relatively stable at the NH4+/NO3- ratio of 50/50. Under the condition of no water stress, the growth of rice seedlings was best at the NH4+/NO3- ratio of 50/50, followed by the NH4+/NO3- ratios of 0/100 and 100/0. [Conclusion] This study will pro- vide a basis for understanding the relationship between water potential and xylem flow. 展开更多
关键词 Rice NH4+/NO3- ratio Water stress Water potential Root-canopy ratio
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In Vitro Study on the Vaporization Ratio of 2-μm Laser in Human Prostatic Tissue
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作者 杨勇 孙东翀 +3 位作者 魏志涛 徐锋 洪宝发 张旭 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第2期198-200,共3页
In this study, the vaporization ratio of the 2-μm laser in the prostatic tissue with benign prostatic hyperplasia was examined in vitro, to explore a technique to estimate the clearance rate of prostatic tissue durin... In this study, the vaporization ratio of the 2-μm laser in the prostatic tissue with benign prostatic hyperplasia was examined in vitro, to explore a technique to estimate the clearance rate of prostatic tissue during the transurethral vaporesection of the prostate. A total of 9 fresh prostatic tissue specimens were obtained by open surgery and the wet weight of the prostatic tissue were measured immediately after the sample collection. Under the simulated conditions of transurethral vaporesection of the prostate by 2-μm laser, each prostate gland was completely vaporesected into fragments with a diameter of less than 1.0 cm in vitro tissue were collected and measured. Then After the vaporesection, the whole fragments of prostatic the lost weight of prostatic tissue, the weight of the collected prostatic tissue and the ratio of the lost weight of prostatic tissue to the wet weight of the prostate glandular organ specimen were calculated. The correlation between the weight of collected prostatic tissue and the weight of the whole glandular organ was analyzed. All the experimental procedures were carried out by one operator. Wet weight of the prostatic gland specimen and the weight of the harvested prostatic tissues after the procedure were recorded. With respect to the wet weight of prostate gland specimen, the percentage of the weight of collected prostatic tissue was (34.45±1.51) %, and the percentage of the lost weight of prostatic tissue was (65.55±1.51)%. Satisfactory linear relationship was observed between the weight of collected prostatic tissue and the wet weight of prostate gland specimen [y=3.245x=6.475 (t=15.097, P=0.000)]. It is concluded that under the simulated conditions of transurethral vaporesection of the prostate by 2-μm laser, the vaporization ratio of prostatic tissue can be calculated on the basis of the weight of collected prostatic tissue, and thereby the clearance of prostatic tissue during the formal operation by 2-μm laser could be quantitatively determined. 展开更多
关键词 2-μm laser benign prostatic hyperplasia VAPORIZATION ratio
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The Paradigm of Surgical Ellipse Dimensions: Are the Length-to-Width Ratio of 3 to 4 and a Vertex Angle of 30&ordm;Correct?
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作者 Tamara R. Tilleman M. M. Tilleman M. H. A. Neumann 《Surgical Science》 2013年第4期236-240,共5页
Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. T... Background: It has been postulated that elliptical cutaneous excisions must possess a length-to-width ratio of 3 to 4 and a vertex angle of 30o or less in order to be closed primarily without creating a “dog ear”. These dimensions became axiomatic in cutaneous surgery and have been taught in the apprenticeship model for years. The present article examines the validity of that paradigm. Methods: We collected data from two sources: ellipses described in the literature (57 cases);and elliptical excisions performed at the authors’ outpatient clinic (83 cases). The surgical ellipse lengths, widths, and vertex angles were analyzed, and the data were compared to a mathematical formula used to generate a fusiform ellipse. Results: The length-to-width ratio of 3 - 4 was found to be inconsistent with the recommended vertex angle of 30o. In fact, a length-to-width ratio of 3 - 4 determines a vertex angle of 48o - 63o. A 30o vertex angle is only feasible with long length-to-width ration of about 7.5. Conclusions: The paradigm that surgical ellipses should have a vertex angle of 30o with length-to-width ratio of 3 - 4 is incorrect. Evidence from actual surgical practice and from mathematical formulation shows that either the length-to-width ratio must be larger than 3 - 4 or the vertex angle must be larger than 30 degrees. 展开更多
关键词 Elliptical EXCISION Length-to-Width ratio of 3 - 4 30o Vertex Angle
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大比例芯-板比的混合夹芯复合材料阴模成型工艺的研究
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作者 顾雪琳 马秘辉 +2 位作者 孟庆杰 王昭军 徐庆石 《纤维复合材料》 CAS 2024年第3期50-55,共6页
本文对大比例芯-板比的混合夹芯复合材料阴模成型工艺进行了研究,以解决该产品R角内部缺陷、泡沫芯材塌陷的产品质量问题,将该产品的R角结构进行了切割打磨,使用光学显微镜观察并分析了阴R角中典型的缺陷结构。开展了预浸料对比试验、R... 本文对大比例芯-板比的混合夹芯复合材料阴模成型工艺进行了研究,以解决该产品R角内部缺陷、泡沫芯材塌陷的产品质量问题,将该产品的R角结构进行了切割打磨,使用光学显微镜观察并分析了阴R角中典型的缺陷结构。开展了预浸料对比试验、R角辅助压实工装对比试验、蜂窝稳定化试验来分析缺陷产生的原理,探索消除R角内部缺陷的方法。此外,还研究了泡沫芯材在常用的复合材料成型工艺参数下的压缩变形情况,探索出了对泡沫进行密封保存以及增加保护盖板厚度的方法来解决其塌陷变形的问题。通过以上研究形成了大比例芯-板比的混合夹芯复合材料阴模成型的优化工艺方法,解决了该产品R角内部缺陷和泡沫塌陷的问题。 展开更多
关键词 夹芯复合材料 混合芯材 大比例芯-板比 阴模成型
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中空制件凸缘高度对挤出吹塑和挤出吹塑-局部抽真空两种成型工艺的影响 被引量:2
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作者 黄虹 李道喜 李敬媛 《真空科学与技术学报》 EI CAS CSCD 北大核心 2013年第11期1086-1090,共5页
以带凸缘的中空制件为研究对象,研究和分析了凸缘的高径比对挤出吹塑和挤出吹塑-局部抽真空两种成型工艺的影响,找到了合理的凸缘高径比值,为中空制件的设计提供了可靠的参数,对挤出吹塑和挤出吹塑-局部抽真空两种成型工艺进行比较,得... 以带凸缘的中空制件为研究对象,研究和分析了凸缘的高径比对挤出吹塑和挤出吹塑-局部抽真空两种成型工艺的影响,找到了合理的凸缘高径比值,为中空制件的设计提供了可靠的参数,对挤出吹塑和挤出吹塑-局部抽真空两种成型工艺进行比较,得出挤出吹塑-局部抽真空成型工艺能增大中空制件凸缘顶部壁厚,降低制件壁厚均方差,提高制件壁厚的均匀性,是一种优化中空制件壁厚分布的有效措施。 展开更多
关键词 挤出吹塑 局部抽真空 中空制件 凸缘高径比 壁厚均匀性
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矩形-八边形组合螺旋箍筋柱抗震性能分析 被引量:3
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作者 陈盛扬 徐浩 +1 位作者 周建龙 薛伟辰 《哈尔滨工程大学学报》 EI CAS CSCD 北大核心 2023年第6期1043-1050,共8页
为研究矩形-八边形组合螺旋箍筋混凝土柱的抗震性能,本文对其(RCC1、RCC4)以及手工绑扎矩形箍筋柱(RCC2、RCC5)、井字形箍筋(RCC3、RCC6)柱开展了0.2、0.8轴压比下足尺低周反复荷载试验研究。结果表明:3种不同箍筋形式的混凝土柱在0.2和... 为研究矩形-八边形组合螺旋箍筋混凝土柱的抗震性能,本文对其(RCC1、RCC4)以及手工绑扎矩形箍筋柱(RCC2、RCC5)、井字形箍筋(RCC3、RCC6)柱开展了0.2、0.8轴压比下足尺低周反复荷载试验研究。结果表明:3种不同箍筋形式的混凝土柱在0.2和0.8轴压比下分别以大偏心压弯破坏、小偏心压弯破坏为标志;在0.2和0.8轴压比下的滞回曲线均较为饱满且在相同轴压比下的耗能基本一致。0.2轴压比下,RCC1的承载力分别比RCC2、RCC3的承载力高2.5%和3.7%,RCC1的位移延性分别比RCC2、RCC3的位移延性高4.6%和2.3%;0.8轴压比下,RCC4的承载力分别比RCC5、RCC6的承载力高4.6%和6.65%,RCC4的位移延性分别比RCC5、RCC6的位移延性高9.5%和4.2%。 展开更多
关键词 矩形-八边形组合螺旋箍筋 自动成型 低周反复荷载试验 抗震性能 滞回曲线 承载力 延性 轴压比
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基于Moldflow的法兰注塑制品翘曲与收缩分析 被引量:1
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作者 王楠 胡泽豪 《轻工机械》 CAS 2013年第3期1-3,7,共4页
以一法兰注塑制品为例,利用Moldflow有限元分析软件分析,得到了法兰注塑制品产生收缩和翘曲的主要原因是收缩。根据注塑成型的4个主要参数,以正交实验为实验方法,再次利用Moldflow有限元分析软件对各个注塑参数组合进行模拟分析,对实验... 以一法兰注塑制品为例,利用Moldflow有限元分析软件分析,得到了法兰注塑制品产生收缩和翘曲的主要原因是收缩。根据注塑成型的4个主要参数,以正交实验为实验方法,再次利用Moldflow有限元分析软件对各个注塑参数组合进行模拟分析,对实验结果数据进行方差分析和信噪比分析,得到最优工艺参数组合。经模拟实验,熔料温度对收缩和翘曲的影响较为显著。 展开更多
关键词 注塑件 收缩 翘曲 工艺参数 正交试验 信噪比
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基于宏-微观尺度黏度模型的微注塑成型工艺参数优化设计 被引量:3
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作者 巫兴悦 刘泓滨 《塑料工业》 CAS CSCD 北大核心 2022年第4期99-103,共5页
选取微泵泵体为研究对象,采用Moldflow有限元软件,修正其黏度模型为宏-微观尺度黏度模型,以优化翘曲变形量为目标,对其微注塑成型过程进行数值模拟。设计基于信噪比的4因素4水平正交试验,结合灰色关联度和均值极差法对实验结果进行分析... 选取微泵泵体为研究对象,采用Moldflow有限元软件,修正其黏度模型为宏-微观尺度黏度模型,以优化翘曲变形量为目标,对其微注塑成型过程进行数值模拟。设计基于信噪比的4因素4水平正交试验,结合灰色关联度和均值极差法对实验结果进行分析,得到模具温度50℃,熔体温度270℃,注射速度80 mm/s,保压压力110 MPa的最佳工艺参数组合,优化后的最小翘曲变形量为0.0795 mm。并得出各因素对微泵泵体质量的影响程度,可排序为保压压力>模具温度>熔体温度(注射速度),为实际微注塑成型提供了加工工艺方面的重要依据。 展开更多
关键词 微注塑成型 -微观尺度黏度模型 微泵泵体 信噪比 灰色关联分析
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PA6/PE-LD共混物流延薄膜成型过程的理论分析与实验研究 被引量:1
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作者 崔同伟 马秀清 《中国塑料》 CAS CSCD 北大核心 2015年第12期62-66,共5页
研究了聚酰胺6/低密度聚乙烯(PA6/PE-LD)共混物流延薄膜成型工艺,从模拟和实验两方面分析了空气间隙和拉伸比对薄膜厚度和颈缩的影响。结果表明,实验和模拟有比较好的吻合性,拉伸比对薄膜厚度的影响大于空气间隙,而空气间隙对薄膜颈缩... 研究了聚酰胺6/低密度聚乙烯(PA6/PE-LD)共混物流延薄膜成型工艺,从模拟和实验两方面分析了空气间隙和拉伸比对薄膜厚度和颈缩的影响。结果表明,实验和模拟有比较好的吻合性,拉伸比对薄膜厚度的影响大于空气间隙,而空气间隙对薄膜颈缩的影响大于拉伸比。 展开更多
关键词 聚酰胺6 低密度聚乙烯 流延薄膜 成型工艺 空气间隙 拉伸比
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Crustal thickness and v_P/v_S ratio in Shanxi Graben, China 被引量:5
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作者 Yutao Shi Yuan Gao Honglin Jing 《Earthquake Science》 2014年第6期589-597,共9页
Shanxi Graben is in the middle part of the North China Craton, from south to north. With the teleseismic data recorded by Regional Seismograph Networks and the temporary ZBnet-W Seismic Array around east part of Shanx... Shanxi Graben is in the middle part of the North China Craton, from south to north. With the teleseismic data recorded by Regional Seismograph Networks and the temporary ZBnet-W Seismic Array around east part of Shanxi Graben, we measured the crustal thickness and Vp/Vs ratio beneath each station using the H-K stack of receiver functions. The observed crustal thickness shows obvious lateral variation, increasing gradually from east to west in the Shanxi Graben. Beneath the Shanxi Graben the crust is relatively thicker than both sides of the south and the north. In addition, the Vp/Vs ratio in the north of study zone is higher than that in the south. The highest Vp/Vs ratio exists in the crust of the Xinding basin and the Datong basin. Our study also suggests that high velocity ratio might result from the strong activities of the magmation and volcanism. 展开更多
关键词 Shanxi Graben North China Craton (NCC) Receiver function Crustal thickness - Crustal Vp/Vs ratio
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Kinetic Modeling the Formation of Low-mature Gases and Analysis of the Possibility to Be Accumulated 被引量:2
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作者 SHUAI Yanhua WANG Hui ZHANG Shuichang SU Aiguo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期537-542,共6页
At present, shallow gases have received much attention due to low cost in exploration and production. Low-mature gases, as one significant origin to shallow gas, turns to be an important research topic. The present un... At present, shallow gases have received much attention due to low cost in exploration and production. Low-mature gases, as one significant origin to shallow gas, turns to be an important research topic. The present understanding of low-mature gases is confined within some geological cases, and few laboratory studies have been reported. Therefore, the potential and characters of low- mature gases are not clear up to now. Here, two premature samples (one coal and the other shale) were pyrolyzed in a gold confined system. The gaseous components including hydrocarbon gases and non-hydrocarbon gases were analyzed. Based on kinetic modeling, the formation of low-mature gases was modeled. The results showed that during low mature stage, about 178 mL/gTOC gas was generated from the shale and 100 mL/gTOC from the coal. Two third to three fourth of the generated gases are non-hydrocarbon gases such as H2S and CO2. The total yields of C1-5 for the two samples are almost the same, 30-40 mL/gTOC, but individual gaseous hydrocarbon is different. The shale has much lower C1 but higher C2-5, whereas the coal has higher C1 but lower C2-5. Hydrocarbon gases formed during low-mature stage are very wet. The stable carbon isotope ratios of methane range from -40‰ to -50‰ (PDB), in good consistence with empiric criterion for low-mature gases summed up by the previous researchers. The generation characters suggest that the low-mature gases could be accumulated to form an economic gas reservoir, but most of them occur only as associated gases. 展开更多
关键词 low-mature gases kinetic modeling carbon isotope ratio of methane potential of C1-5
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