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Necrosis zone depth after bipolar plasma vaporization and resection in the human prostate
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作者 Clara Breitling Hans Nenning Jorg Rassler 《Asian Journal of Urology》 CSCD 2023年第2期144-150,共7页
Objectives:To compare the depth of thermal necrosis after use of bipolar resection and vaporization technique comparing intra-individually bipolar loop and bipolar button electrodes.Methods:Transurethral resection and... Objectives:To compare the depth of thermal necrosis after use of bipolar resection and vaporization technique comparing intra-individually bipolar loop and bipolar button electrodes.Methods:Transurethral resection and vaporization of the prostate was performed in 55 male patients(260 specimens in total).In a standardized procedure,a bipolar resection loop was used for resection,and a bipolar button electrode was used for vaporization.Both electrodes were applied in each patient,either in the left or in the right lateral lobe.The depth of necrotic zones in the resected or vaporized tissue of each patient was measured in a standardized way by light microscopy.Results:The mean depth with standard deviation of thermal injury caused by the loop electrode was 0.0495±0.0274 mm.The vaporization electrode caused a mean thermal depth with standard deviation of 0.0477±0.0276 mm.The mean difference of necrosis zone depths between the two types of electrodes(PlasmaButtoneresection loop)was 0.0018 mm(p=0.691).Conclusion:For the first time,we present directly measured values of the absolute necrosis zone depth after application of plasma in the transurethral treatment of benign prostatic hyperplasia.The measured values were lower than in all other transurethral procedures.Standardized procedures of measurement and evaluation allow a statistically significant statement that the low necrosis depth in bipolar procedures is independent of the applied electrodes. 展开更多
关键词 Transurethral resection of prostate Bipolar enucleation Plasma resection Plasma vaporization Necrosis depth
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Emphysematous sloughed floating ball after prostate water vaporization Rezum:A case report
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作者 Mansour Alnazari Abdulaziz Bakhsh Emad Sabri Rajih 《World Journal of Clinical Cases》 SCIE 2023年第23期5525-5529,共5页
BACKGROUND Rezūm™water vapor therapy is a new minimally invasive endoscopic technology for the management and treatment of benign prostatic hyperplasia.CASE SUMMARY A 63-year-old male presented to our department with... BACKGROUND Rezūm™water vapor therapy is a new minimally invasive endoscopic technology for the management and treatment of benign prostatic hyperplasia.CASE SUMMARY A 63-year-old male presented to our department with severe dysuria,frequency,urgency,and interrupted stream 2 mo after receiving Rezūm™therapy.The symptoms were caused by a retained floating emphysematous necrotic sloughed tissue.We also discovered a persistent bacterial infection that was resistant to parenteral antimicrobial therapy.The treatment of the patient included surgical removal of the necrotic tissue.CONCLUSION Despite the good safety profile and minimal adverse events related to Rezūm™therapy,major complications can still occur. 展开更多
关键词 Benign prostatic hyperplasia Rezum Lower urinary tract symptoms Minimally invasive therapy Water vapor therapy Transurethral resection of the prostate Case report
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Evaluation of greenlight photoselective vaporization of the prostate for the treatment of high-risk patients with benign prostatic hyperplasia 被引量:12
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作者 Wei-Jun Fu Bao-Fa Hong Xiao-Xiong Wang Yong Yang Wei Cai Jiang-Ping Gao Yao-Fu Chen Cui-E Zhang 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第3期367-371,共5页
Aim: To explore the feasibility and safety of greenlight photoselective vaporization of the prostate (PVP) on high-risk patients presenting with lower urinary tract symptoms suggestive of benign prostatic hyperplas... Aim: To explore the feasibility and safety of greenlight photoselective vaporization of the prostate (PVP) on high-risk patients presenting with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH) and to evaluate their clinical and voiding outcome. Methods: A total of 85 high-risk patients with obstructive BPH underwent PVP with an 80 W potassium-titanyl-phosphate laser, which was delivered through a side-deflecting fiber with a 23 Fr continuous flow cystoscope. Operative time, blood loss, indwelling catheterzation, international prostate symptom score (IPSS), quality of life score (QoL), uroflowmetry, postvoid residual urine volume and short-term complication rates were evaluated for all patients. Results: All patients got through the perioperative period safely. The chief advantages of PVP were: short operative time (25.6 ± 7.6 min), little bleeding loss (56.8 ± 14.3 mL) and short indwelling catheterization (1.6 ± 0.8 d). The IPSS and QoL decreased from (29.6 ± 5.4) and (5.4 ± 0.6) to (9.5 ± 2.6) and (1.3 ± 0.6), respectively. The vast majority of patients were satisfied with voiding outcome. The mean maximal urinary flow rate increased to 17.8 mL/s and postvoid residual urine volume decreased to 55.6 mL. These results are significantly different from preoperative data (P 〈 0.05). No patient required blood transfusion or fluid absorption. There were few complications and very high patient satisfaction after operation. Conclusion: PVP has a short operative time and high tolerance, and is safe, effective and minimally invasive for high-risk patients, therefore it might be considered as a good alternative treatment for high-risk patients with obstructive urinary symptoms as a result of BPH. 展开更多
关键词 benign prostatic hyperplasia photoselective vaporization of the prostate HIGH-RISK laser surgery PROSTATE
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Thermal behaviors and heavy metal vaporization of phosphatized tannery sludge in incineration process 被引量:11
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作者 TANG, Ping ZHAO, Youcai XIA, Fengyi 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第9期1146-1152,共7页
The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosph... The high concentration of heavy metal (Cu, Cr, Zn, Pb) in tannery sludge causes severe heavy metal emissions in the process of incineration. In the present investigation, the tannery sludge was treated with 85% phosphoric acid before the incineration process in the tube furnace to control the heavy metal emissions. The thermal behavior and heavy metal vaporization of pre-treated tannery sludge were investigated, and X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were also implemente... 展开更多
关键词 tannery sludge thermal behavior heavy metal vaporization phosphatation
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Vaporization behavior of lead from the FeO-CaO-SiO_2-Al_2O_3 slag system 被引量:3
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作者 Yanling Zhang Rui Zhang +1 位作者 Eiki Kasai Shiqi Li 《Journal of University of Science and Technology Beijing》 CSCD 2008年第6期671-677,共7页
Vaporization behavior (1163-1463 K) of lead in the slag system of FeO-CaO-SiO2-Al2O3 with CaC% was examined. A thermodynamic estimation with the principle of Gibbs free energy minimization showed that the major vapo... Vaporization behavior (1163-1463 K) of lead in the slag system of FeO-CaO-SiO2-Al2O3 with CaC% was examined. A thermodynamic estimation with the principle of Gibbs free energy minimization showed that the major vapor species from the sample of the FeO-CaO-SiO2-Al2O3 system+PbO+CaCl2 were metallic Pb, PbCl, PbCl2, and FeCl2, at the experimental temperature range. The experimental results show that the mole ratio of vaporized Cl in lead chlorides to vaporized Pb, simply expressed as Cl/Pb decreases with increasing temperature. The larger Cl/Pb means a larger ratio of gaseous PbCl2, since metallic Pb and PbCl vapors are formed in a similar reduction atmosphere. The evaporation is initially rapid and becomes steady after holding for 10 min. Gaseous PbCl2 is mainly formed during the heating period, and at the holding stage, it reacts with FeO to produce gaseous FeCl2 With regard to slag composition, FeO content and basicity significantly affect the evaporation of lead. High FeO content and high basicity promotes the formation of metallic Pb and PbCI, whereas, it prohibits PbCl2 evaporation. 展开更多
关键词 slag system smelting process vaporization behavior LEAD
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Treatment satisfaction after I year high-power potassiumtitanyl-phosphate photoselective vaporization of the prostate 被引量:1
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作者 Ja Hyeon Ku Min Chul Cho Hyeong Seok Kim Jae-Seung Paick Soo Woong Kim 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第5期728-734,共7页
To investigate the factors that influence treatment satisfaction after high-power potassium-titanyl-phosphate (KTP) laser vaporization of the prostate, we compared the characteristics between patients who were satis... To investigate the factors that influence treatment satisfaction after high-power potassium-titanyl-phosphate (KTP) laser vaporization of the prostate, we compared the characteristics between patients who were satisfied and those who were not satisfied. In all, 97 patients aged between 53-82 years (median age 67 years) underwent high-power KTP laser vaporization of the prostate for lower urinary tract symptoms due to benign prostatic hyperplasia. At 12 months postoperatively, 60 patients were satisfied with the treatment, whereas 37 were dissatisfied. Although there were no differences in International Prostate Symptom Score (IPSS) values at baseline, the satisfied group scored better in total IPSS at 1, 3, 6, and 12 months postoperatively (P 〈 0.05). At baseline, the maximum flow rate (Qmax) was lower in the dissatisfied group and remained low throughout the follow-up period, with the exception of 1 month postoperatively (P 〈 0.05), compared with the satisfied group. There were no differences in other objective data between the two groups, including post-void residual and the number of voids based on the frequency-volume charts. In a multivariate model, a higher bladder contractility index was associated with a greater likelihood of treatment satisfaction 12 months after high-power KTP laser vaporization (odds ratio 1.024, 95% confidence interval 1.001-1.048, P 〈 0.05). Patients who were not satisfied following the surgery had a smaller improvement in subjective symptoms and Qmax. In addition, our findings suggest that the relative risk of treatment dissatisfaction following high-power KTP laser vaporization was increased in patients with weak detrusor contractility. 展开更多
关键词 benign prostatic hyperplasia potassium-titanyl-phosphate PROSTATE SATISFACTION vaporization
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Determination of Trace Rare Earth Elements in Biological Samples by ICP-AES with Tungsten-spiral Electrothermal Vaporization Sampling 被引量:1
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作者 梅二文 刘慧 +1 位作者 廖振环 江祖成 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第1期52-57,共6页
A method for determination of trace rare earth elements in biological sample by ICP-AES with tungsten-spiral electrothermal vaporization(TETV-ICP-AES)sampling has been developed in this work. Several influencing facto... A method for determination of trace rare earth elements in biological sample by ICP-AES with tungsten-spiral electrothermal vaporization(TETV-ICP-AES)sampling has been developed in this work. Several influencing factors including desolvation and vaporization parameters,carrier gas flow rate and ma- trix effect were investigated in detail.Under optimal experimental conditions,the detection limits for La,Nd, Gd,Dy,Ho,Yb,Lu and Y were obtained in the range of 10^(-9)~10^(-11) g,and they are comparable to and,in most instances,better than those for the GFAAS and conventional pneumatic nebulisation-ICP-AES.The precision(RSD)obtained for this method is less than 6%. 展开更多
关键词 Tungsten-spiral electrothermal vaporization sampling ICP-AES REE Biological sample
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Carbon isotopic fractionation during vaporization of low molecular weight hydrocarbons(C6–C12)
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作者 Qian-Yong Liang Yong-Qiang Xiong +2 位作者 Jing Zhao Chen-Chen Fang Yun Li 《Petroleum Science》 SCIE CAS CSCD 2017年第2期302-314,共13页
Three series of laboratory vaporization experiments were conducted to investigate the carbon isotope fractionation of low molecular weight hydrocarbons(LMWHs)during their progressive vaporization.In addition to the ... Three series of laboratory vaporization experiments were conducted to investigate the carbon isotope fractionation of low molecular weight hydrocarbons(LMWHs)during their progressive vaporization.In addition to the analysis of a synthetic oil mixture,individual compounds were also studied either as pure single phases or mixed with soil.This allowed influences of mixing effects and diffusion though soil on the fractionation to be elucidated.The LMWHs volatilized in two broad behavior patterns that depended on their molecular weight and boiling point.Vaporization significantly enriched the ^13C present in the remaining components of the C6–C9 fraction,indicating that the vaporization is mainly kinetically controlled;the observed variations could be described with a Rayleigh fractionation model.In contrast,the heavier compounds(n-C10–n-C12)showed less mass loss and almost no significant isotopic fractionation during vaporization,indicating that the isotope characteristics remained sufficiently constant for these hydrocarbons to be used to identify the source of an oil sample,e.g.,the specific oil field or the origin of a spill.Furthermore,comparative studies suggested that matrix effects should be considered when the carbon isotope ratios of hydrocarbons are applied in the field. 展开更多
关键词 Low molecular weight hydrocarbons Gas chromatography-isotope ratio mass spectrometry Isotope fractionation vaporization
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VAPORIZATION HEAT AT NORMAL BOILING POINT AND MOLECULAR TOPOLOGY FOR PARAFFINS
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作者 Deng Gao JIANG Cai Rong ZHOU Fu An WANG (Department of Chemical Engineering, Zhengzhou, Institute. of Technology, Zhengzhou. 450002) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第6期519-522,共4页
According to graph theory method, new method is proposed for the prediction or vaporization heat at normal boiling point of paraffins with moleeular,atructure, and it is compared with other methods. We predict the. va... According to graph theory method, new method is proposed for the prediction or vaporization heat at normal boiling point of paraffins with moleeular,atructure, and it is compared with other methods. We predict the. vaporization heat at normal boiling point for 57 different paraffins, and that is compared with experimental data, its overall, absolute average deviation is 0.61%. The result is,superior to other methods. 展开更多
关键词 HEAT vaporization BOILING AND
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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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Determination of Trace Amount of Vanadium in High Purity Y_2O_3 by Electrothermal Vaporization-ICP-AES With Bi(PDC)_3 Coprecipitation
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作者 胡斌 杨波涌 +2 位作者 曾纪铭 江祖成 曾云鹗 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第1期47-51,共5页
A new method for the determination of vanadium in high purity Y2O3 by fluorination assisted electrothermal vaporization-ICP-AES is presented in this paper. After the sample dissolved,the vanadium in the sample solutio... A new method for the determination of vanadium in high purity Y2O3 by fluorination assisted electrothermal vaporization-ICP-AES is presented in this paper. After the sample dissolved,the vanadium in the sample solution was coprecipitated with Bi(PDC)_3 at pH 3. 7. The precipitates were made into a slurry with the fluorinating agent PTFE and directly introduced into the graphite furnace for determination. The analytical results were obtained by aqueous calibration curve method. The detection limit of the method is 1. 1 ng/mL, the RSD is 2. 8% (n=10,1 5 ng/mL vanadium solution), and the recovery of vanadium added to real sample is more than 96%. 展开更多
关键词 Bi(PDC)_3 coprecipitation Electrothermal vaporization Plasma spectrometry Vanadium Polytetrafluoroethylene High purity Y_2O_3
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Determination of Cd,Pb and Sr by Microwave Plasma Torch Atomic Emision Spectrometry Using an Electrothermal Vaporization Sample Introduction System
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作者 ZHAO Li-wei ZHANG Han-qí +4 位作者 CAO Yan-bo YANG Wen-jun JIN Qun JIN Qin-han FU Yao 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第4期22-26,共5页
A method for the determination of Cd,Pb and Sr by microwave plasma torch(MPT)atomic emission spectrometry(AES)was developed.Th e samples were introduced into the MPT with an elec trothermal vaporization(ETV)device.The... A method for the determination of Cd,Pb and Sr by microwave plasma torch(MPT)atomic emission spectrometry(AES)was developed.Th e samples were introduced into the MPT with an elec trothermal vaporization(ETV)device.The effects of some experimental conditions on the de-termination of Cd,Pb and Sr were examined.The effects of easily ionized elements on the emis-sion intensity of Cd,Pb and Sr were studied in detail.The detection limits for Cd,Pb and Sr are 2.4,4.0 and 1.3 ng/mL,respectively. 展开更多
关键词 Atomic emission spectrometry Microwave plasma torch Electrothermal vaporization
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Calculation of vaporization pressure in laser penetration welding of 304 stainless steel
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作者 段爱琴 张朴 陈俐 《China Welding》 EI CAS 2010年第2期42-46,共5页
Many research results have revealed that vaporization pressure has important effects on the formation of the keyhole and molten pool during laser welding. In this paper, based on law of conservation of energy, an inno... Many research results have revealed that vaporization pressure has important effects on the formation of the keyhole and molten pool during laser welding. In this paper, based on law of conservation of energy, an innovative physical model is found to calculate the vaporization pressure during laser welding. In this model, vaporization pressure can be calculated according to some characteristics of the spatter particle. These features include the size, velocity and displacement. They can be measured through images taken by high-speed camera. The periods of this pressure also measured by counting opening and closing time of the bottom keyholes. At this welding condition, the typical vaporization pressure is about 20 203 Pa and the period is about 6. 9 ms. The average opening time of bottom keyholes is about 4. 3 ms, and the closing time is about 2. 6 ms. 展开更多
关键词 laser welding KEYHOLE vaporization pressure opening and closing time
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Three-dimensional transient simulation of CO_(2) laser tissue vaporization and experimental evaluation with a hydrogel phantom
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作者 Kazuma Sudo Yu Shimojo +1 位作者 Takahiro Nishimura Kunio Awazu 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2022年第3期1-9,共9页
A quantitative analysis method of CO_(2) laser treatments promotes laser treatment performance and rapid clinical application of novel treatment devices.The in silico clinical trial approach,which is based on computat... A quantitative analysis method of CO_(2) laser treatments promotes laser treatment performance and rapid clinical application of novel treatment devices.The in silico clinical trial approach,which is based on computational simulation of light-tissue interactions using the mathematical model,can provide quantitative data.Although several simulation methods of laser tissue vaporization with CO_(2) laser treatments have been proposed,validations of the CO_(2) laser wavelength have been insuffcient.In this study,we demonstrated a tissue vaporization simulation using a CO_(2) laser and performed the experimental validation using a hydrogel phantom with constant physical parameters to evaluate the simulation accuracy of the vaporization process.The laser tissue vaporization simulation consists of the calculation of light transport,photothermal conversion,thermal diffusion,and phase change in the tissue.The vaporization width,depth,and area with CO_(2) laser irradiation to a tissue model were simulated.The simulated results differed from the actual vaporization width and depth by approximately 20%and 30%,respectively,because of the solubilization of the hydrogel phantom.Alternatively,the simulation vaporization area for all light irradiation parameters,which is related to the vaporization amount,agreed well with the actual vaporization values.These results suggest that the computational simulation can be used to evaluate the amount of tissue vaporization in the safety and effectiveness analysis of CO_(2) laser treatments. 展开更多
关键词 Laser tissue vaporization in silico clinical trial hydrogel phantom CO_(2)laser
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The Effect of Atmospheric Oxygen on the Puffing and Bursting Phenomena during Vegetable Oils Droplets Vaporization Process for Their Use as Biofuel in Diesel Engine
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作者 A. S. Zongo T. Daho +6 位作者 G. Vaitilingom B. Piriou J. Valette C. Caillol B. G. Segda P. Higelin J. Koulidiati 《Energy and Power Engineering》 2018年第12期518-533,共16页
The past literature on the use of vegetable oils as fuel in diesel engine revealed that utilizing vegetable oil fuels in diesel engines may require property changes in the oil or perhaps, some minor engine modificatio... The past literature on the use of vegetable oils as fuel in diesel engine revealed that utilizing vegetable oil fuels in diesel engines may require property changes in the oil or perhaps, some minor engine modifications or operating changes. This study was conducted to search for the effect of atmospheric oxygen on the puffing and bursting phenomena that occur during vegetable oils droplet vaporization process in their use as fuel in diesel engine. The fiber-suspended droplet technique was used, and the normalized square droplet diameter as well as the temperature evolution vicinity the droplet was analyzed. The results show that puffing and bursting phenomena highly depend on oxygen. In presence of atmospheric oxygen, there is an increase of the puffing and bursting intensity and therefore the evaporation rate of the vegetable oil droplets, but in an inert environment or when the environment is oxygen-depleted puffing and bursting phenomena disappearing and make place of a series of explosions with lower magnitude. The lack of oxygen reduces the thermal degradation, polymerization and oxidation reactions and consequently the vaporization rate of vegetable oils droplets;and could therefore lead to the formation of deposits in the form of polymers. This is unsuitable for their use as a fuel in diesel engines. It can also be concluded that atmospheric oxygen has some positive effects on engine performance and emissions when operating with vegetable oil. These results help to address the challenge for the use of alternative fuels such as non-edible vegetable oils. 展开更多
关键词 PUFFING BURSTING Oxygen Nitrogen LINSEED Oil vaporization Engine Energy
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STUDY OF EXPLOSIVE VAPORIZATION OF LD11R ALUMINUMALLOY DURING ELECTRON BEAM DEEP PENETRATION
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作者 Wang, Y.J. Jia, S.J. +1 位作者 Liu, F.J. Chen, X.F. 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2000年第6期1119-1124,共6页
High-power-density electron beam with single pulse was performed on the LD11R aluminum alloy. The electron beam was focused on three typical positions. For each case, the distribution of the solute concentration at th... High-power-density electron beam with single pulse was performed on the LD11R aluminum alloy. The electron beam was focused on three typical positions. For each case, the distribution of the solute concentration at the cavity bottom solid-liquid interface was investigated by using the 'rapidly fixing' method. The interaction of the beam and solute atoms was analyzed. A new mechanism of explosive vaporization was proposed based on the present results. The occurrence of this explosive vaporization source was discussed. 展开更多
关键词 Electron beam welding vaporization
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Mass Spectrometric Study of Clusters Produced by Laser Vaporization of Some Phosphates
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作者 Xiang Hong LIU Xiao Guang ZHANG +2 位作者 Yue LI Xiu Yan WANG and Nan Quan LOU(State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第9期805-806,共2页
The clusters generated by direct laser vaporization of KH2PO4 and Cu-3(PO4)(2) samples are studied by a TOF mass spectrometer. It is found that mainly the [K(KPO3)(n)]* cluster series is generated from KH2PO4 sample a... The clusters generated by direct laser vaporization of KH2PO4 and Cu-3(PO4)(2) samples are studied by a TOF mass spectrometer. It is found that mainly the [K(KPO3)(n)]* cluster series is generated from KH2PO4 sample and it demonstrates obvious magic numbers, which are n=3, 6, 9, 12, 15. Direct laser vaporization of Cu-3(PO4)(2) sample produced [Cu(CuPO3)n]* cluster series as well as other series with the same building block of (CUPO3). 展开更多
关键词 Mass Spectrometric Study of Clusters Produced by Laser vaporization of Some Phosphates KPO
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Characterization and Evaluation of Standard Enthalpy of Vaporization and Kinetic Studies of Volatile bis(<i>N</i>-ethyl-5-methyl-salicylaldimine)nickel(II) Complex
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作者 Thevabakthi Siluvai Muthu Arul Jeevan Maria Francis George Johnson +2 位作者 Atnafu Guadie Assefa Sebastian Arockiasamy Karachalacheruvu Seetharamaiah Nagaraja 《American Journal of Analytical Chemistry》 2015年第2期156-163,共8页
The bis(N-ethyl-5-methylsalicylaldimine)nickel(II) [Ni(5-me-saletN)2] complex was synthesized and characterized by elemental analyses, FT-IR, TG-DTA, mass spectrometry and vapour pressure measurement studies. The TG c... The bis(N-ethyl-5-methylsalicylaldimine)nickel(II) [Ni(5-me-saletN)2] complex was synthesized and characterized by elemental analyses, FT-IR, TG-DTA, mass spectrometry and vapour pressure measurement studies. The TG curve of the complex showed a single-step weight loss commencing from 490 K to nil residue at 600 K, without competing fragmentation step. The non-isothermal vaporization activation energy value determined by Coats-Redfern method yielded the value of 93.5 ± 7 kJmol–1. The dynamic TG run proved the complex to be completely volatile. And the equilibrium vapour pressure of the complex over the temperature range of 421 - 524 K, determined by the TG-based transpiration technique yielded the value of 94.2 ± 1.2 kJmol–1 for its standard enthalpy of vaporization . The entropy of vaporization was calculated from the intercept and found to be 249.4 ± 2.6 Jmol–1&bull;K–1. 展开更多
关键词 NICKEL Complexes Enthalpy of vaporization THERMOGRAVIMETRY Vapour Pressure Kinetic Studies
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Interest of Splitting the Enthalpies of Vaporization in Four Distinct Parts Reflecting the Van der Waals and the Hydrogen Bonding Forces
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作者 Paul Laffort 《Open Journal of Physical Chemistry》 2020年第2期117-137,共21页
An experimental characterization of the Van der Waals forces involved in volatile organic compounds (VOC) dissolved into stationary phases of gas liquid chromatography (GLC) has been started at the beginning of the se... An experimental characterization of the Van der Waals forces involved in volatile organic compounds (VOC) dissolved into stationary phases of gas liquid chromatography (GLC) has been started at the beginning of the seventies. This field has been reactivated from 1994 thanks to a fruitful cooperation between our CNRS team and the group of Ervin Kováts at the Federal Polytechnic School of Lausanne. The applied strategy can be summarized, in the first instance, as the experimental measurement of accurate and superabundant mutual affinities of a limited number of VOC and stationary phases and their processing using an original tool named Multiplicative Matrix Analysis (MMA). Then, in the second stage, the obtained results have been compared with molecular properties well established, as the Van der Waals molecular volume, the refraction index and the polar surface area (PSA), in order to get generalized values for any compound. The present study summarizes the positive results developed in our three last papers on this topic (2013, 2016 and 2018), as well as the attempt to overcome the negative ones using enthalpies of vaporization. 展开更多
关键词 Enthalpy of vaporization Van der WAALS Intermolecular FORCES Molecular Polarity Polar Surface Area GAS-LIQUID Chromatography Chemo-Informatics OLFACTION
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Vaporization and Thermodynamics of Glass-Forming Oxide Melts: Mass Spectrometric Study and Modeling
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作者 V. L. Stolyarova 《Journal of Materials Science and Chemical Engineering》 2015年第7期81-86,共6页
Information on the vaporization processes and thermodynamic properties of glass-forming oxide melts in the systems MgO-B2O3-SiO2, CaO-B2O3-SiO2, SrO-B2O3-SiO2, BaO-B2O3-SiO2, PbO-B2O3-SiO2, CdO-B2O3-SiO2, ZnO-B2O3-SiO... Information on the vaporization processes and thermodynamic properties of glass-forming oxide melts in the systems MgO-B2O3-SiO2, CaO-B2O3-SiO2, SrO-B2O3-SiO2, BaO-B2O3-SiO2, PbO-B2O3-SiO2, CdO-B2O3-SiO2, ZnO-B2O3-SiO2, Bi2O3-B2O3-SiO2 and Bi2O3-GeO2-SiO2 together with the earlier obtained data is discussed. These data were obtained by high-temperature mass spectrometric method. Various types of vapor species were found over oxide systems studied such as the associated, dissociated and polymerized products of vaporization. The regularities of the vaporization of the binary and multicomponent glass-forming oxide melts were illustrated and discussed from the point of view of the acid-base concept. Results on determination of thermodynamic functions in oxide systems were considered taking into account the main requirements for the confirmation of their reliability. The generalized lattice theory of associated solutions was used for the calculation of thermodynamic properties of the ternary silicate melts studied. Using this approach the different levels of deviations from the ideality in the melts under investigation were clarified. The relative numbers of bonds of various types formed in the melts considered were also calculated based on the generalized lattice theory of associated solutions. 展开更多
关键词 GLASS-FORMING OXIDE MELTS Thermodynamics vaporization High Temperature MASS Spectrometry
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