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期刊论文 17

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医院中子照射器I型堆 2

NOx 1

中国实验快堆 1

中子通量密度 1

增殖堆 1

快堆发展战略 1

永磁同步发电机；径向通风孔；转矩脉动；分段斜极；磁体形状优化；有限元分析；风电 1

浓淡燃烧 1

热中子束流孔道 1

燃烧器 1

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Exergy-energy analysis of full repowering of a steam power plant

S. NIKBAKHT NASERABAD,K. MOBINI,A. MEHRPANAHI,M. R. ALIGOODARZ

《能源前沿（英文）》 2015年 第9卷 第1期   页码 54-67 doi: 10.1007/s11708-014-0342-6

摘要： A 320 MW old steam power plant has been chosen for repowering in this paper. Considering the technical conditions and working life of the power plant, the full repowering method has been selected from different repowering methods. The power plant repowering has been analyzed for three different feed water flow rates: a flow rate equal to the flow rate at the condenser exit in the original plant when it works at nominal load, a flow rate at maximum load, and a flow rate when all the extractions are blocked. For each flow rates, two types of gas turbines have been examined: V94.2 and V94.3A. The effect of a duct burner has then been investigated in each of the above six cases. Steam is produced by a double-pressure heat recovery steam generator (HRSG) with reheat which obtains its required heat from the exhaust gases coming from the gas turbines. The results obtained from modeling and analyzing the energy-exergy of the original steam power plant and the repowered power plant indicate that the maximum efficiency of the repowered power plant is 52.04%. This maximum efficiency occurs when utilizing two V94.3A gas turbines without duct burner in the steam flow rate of the nominal load.

关键词： full repowering     exergy analysis     V94.2 and V94.3A gas turbines     double-pressure HRSG     duct burner     Bandarabbas steam power plant     efficiency    

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Bile duct injury repair — earlier is not better

null

《医学前沿（英文）》 2015年 第9卷 第4期   页码 508-511 doi: 10.1007/s11684-015-0418-7

摘要：

Bile duct injury is a common complication of cholecystectomy. The timing of bile duct injury repair remains controversial. A recent review conducted in France reported 39% complications and 64% failure after immediate repair in 194 patients compared with 14% complications and 8% failure after late repair in 133 patients. A national review of 139 consecutive early repairs conducted at five hepatopancreaticobiliary centers in Denmark reported 4% mortality, 36% morbidity, and 42 restrictures (30%) at a median follow-up of 102 months, and only 64 patients (46%) demonstrated uneventful short-term and long-term outcomes. Most patients with bile duct injury present with bile leak and sepsis; thus, early repair is not recommended. Percutaneous drainage of bile and endoscopic stenting are the mainstays of treatment of bile leak because they convert acute bile duct injury into a controlled external biliary fistula. The ensuing benign biliary stricture should be repaired by a biliary surgeon after a delay of 4–6 weeks once the external biliary fistula has closed.

关键词： bile duct injury     cholecystectomy     laparoscopic cholecystectomy    

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A giant Müllerian duct cyst in the perineum: a case report

null

《医学前沿（英文）》 2012年 第6卷 第4期   页码 440-443 doi: 10.1007/s11684-012-0222-6

摘要：

The authors present a case report of a giant Müllerian duct cyst in the perineum. A 37-year-old man presented with a mass with the size of 50 cm×40 cm×30 cm in the perineum. Computed tomography (CT) scan and magnetic resonance imaging (MRI) of the pelvis and perineum found a huge multilocular cystic mass. X-ray film of the pelvis showed a giant soft-tissue shadow of high density in the perineum. Voiding cystourethrogram did not show any cyst interlinked to posterior urethra. After related examinations, the patient underwent open surgical resection of the cyst. Pathologic examination confirmed the presence of a Müllerian duct cyst. Huge Müllerian duct cyst is uncommon in clinic. Treatments of Müllerian duct cysts depend on their sizes and symptoms.

关键词： Müllerian duct cyst     clinical symptoms     diagnosis    

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Influence of mass air flow ratio on gas-particle flow characteristics of a swirl burner in a 29 MW pulverized

Rong YAN, Zhichao CHEN, Shuo GUAN, Zhengqi LI

《能源前沿（英文）》 2021年 第15卷 第1期   页码 68-77 doi: 10.1007/s11708-020-0697-9

摘要： In a gas/particle two-phase test facility, a three-component particle-dynamics anemometer was used to measure the characteristics of gas/particle two-phase flows in a 29 megawatt (MW) pulverized coal industrial boiler equipped with a new type of swirling pulverized coal burner. The distributions of three-dimensional gas/particle velocity, particle volume flux, and particle size distribution were measured under different working conditions. The mean axial velocity and the particle volume flux in the central region of the burner outlet were found to be negative. This indicated that a central recirculation zone was formed in the center of the burner. In the central recirculation zone, the absolute value of the mean axial velocity and the particle volume flux increased when the external secondary air volume increased. The size of the central reflux zone remained stable when the air volume ratio changed. Along the direction of the jet, the peak value formed by the tertiary air gradually moved toward the center of the burner. This tertiary air was mixed with the peak value formed by the air in the adiabatic combustion chamber after the cross-section of / = 0.7. Large particles were concentrated near the wall area, and the particle size in the recirculation zone was small.

关键词： industrial pulverized coal boiler     swirl burner     air/particle flow     particle dynamic analyzer (PDA)    

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Diagnosis and treatment of thyroglossal duct carcinoma: Report of three cases with review of literatures

GAO Yan, CHEN Yan, SUN Zhipeng, GUO Chuanbin, YU Guangyan, ZHAN Yi

《医学前沿（英文）》 2008年 第2卷 第1期   页码 58-62 doi: 10.1007/s11684-008-0011-4

摘要： Thyroglossal duct carcinoma, which is usually diagnosed postoperatively, is a rare malignant tumor arising in the thyroglossal duct cyst. The definitive diagnosis can be made only after microscopic examination. We retrospectively reviewed three cases of thyroglossal duct carcinoma diagnosed in Peking University School and Hospital of Stomatology from January 1986 to August 2006. Clinical and pathological features were investigated and the optimal treatment protocol was proposed. The constituent ratio of thyroglossal duct carcinoma among surgically excised thyroglossal duct lesions was 2.9%. The clinical presentation of thyroglossal duct carcinoma was very similar to that of its benign counterpart. Two cases were diagnosed as thyroglossal duct cyst prior to the operation, the remaining one as dermoid cyst. All three cases were diagnosed as papillary carcinoma of thyroid origin after microscopic examination. Primary thyroglossal duct carcinoma should conform to the following criteria: localization of the carcinoma to a clearly demonstrable thyroglossal duct cyst or tract; clinically or histologically confirmed absence of carcinoma of the thyroid gland. Papillary carcinoma is the most common histological type, which usually develops slowly with an excellent prognosis. The histological characteristics including: formation of papillary structure; nuclear morphological variations such as ground glass nuclei, pseudoinclusions, intranuclear grooves and filaments; concentrically calcified structures termed psammoma bodies which is regarded as a strong indication of papillary carcinoma; and positivity in immunohistological staining for thyroglobin. Sistrunk procedure of excision is the choice for treatment. A close follow-up is needed. In the presence of thyroid gland masses or cervical lymphadenopathy, thyroidectomy or neck dissection should be recommended. The effect of thyroid suppression therapy and radioactive iodine therapy is not conclusive.
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Numerical simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

《能源前沿（英文）》 2012年 第6卷 第3期   页码 296-303 doi: 10.1007/s11708-012-0191-0

摘要： The progression of ignition was numerically simulated with the aim of realizing a full-scale tiny-oil ignition burner that is identical to the burner used in an 800 MWe utility boiler. The numerical simulations were conducted for four excess air ratios, 0.56, 0.75, 0.98 and 1.14 (corresponding to primary air velocities of 17, 23, 30 and 35 m/s, respectively), which were chosen because they had been used previously in practical experiments. The numerical simulations agreed well with the experimental results, which demonstrate the suitability of the model used in the calculations. The gas temperatures were high along the center line of the burner for the four excess air ratios. The flame spread to the burner wall and the high-temperature region was enlarged in the radial direction along the primary air flow direction. The O concentrations for the four excess air ratios were 0.5%, 1.1%, 0.9% and 3.0% at the exit of the second combustion chamber. The CO peak concentration was very high with values of 7.9%, 9.9%, 11.3% and 10.6% for the four excess air ratios at the exit of the second combustion chamber.

关键词： numerical simulation     tiny-oil ignition burner     pulverized coal     temperature field    

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Strategies of minimally invasive treatment for intrahepatic and extrahepatic bile duct stones

null

《医学前沿（英文）》 2017年 第11卷 第4期   页码 576-589 doi: 10.1007/s11684-017-0536-5

摘要：

Cholelithiasis is a kind of common and multiple diseases. In recent years, traditional laparotomy has been challenged by a minimally invasive surgery. Through literature review, the therapeutic method, effect, and complications of minimally invasive treatment of intrahepatic and extrahepatic bile duct stones by combining our practical experience were summarized as follows. (1) For intrahepatic bile duct stones, the operation may be selected by laparoscopic liver resection, laparoscopic common bile duct exploration (LCBDE), or percutaneous transhepatic cholangioscopy. (2) For concomitant gallstones and common bile duct stones, the surgical approach can be selected as follows: laparoscopic cholecystectomy (LC) combined with endoscopic sphincterotomy (EST) or endoscopic papillary balloon dilatation, LC plus laparoscopic transcystic common bile duct exploration, LC plus LCBDE, and T-tube drainage or primary suture. (3) For concomitant intrahepatic and extrahepatic bile duct stones, laparoscopic liver resection, choledochoscopy through the hepatic duct orifice on the hepatectomy cross section, LCBDE, EST, and percutaneous transhepatic cholangioscopic lithotripsy could be used. According to the abovementioned principle, the minimally invasive treatment approach combined with the surgical technique and equipment condition will be significant in improving the therapeutic effect and avoiding the postoperative complications or hidden dangers of intrahepatic and extrahepatic bile duct stones.

关键词： laparoscopy     choledochoscopy     duodenoscopy     cholelithiasis     minimally invasive treatment    

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Development and demonstration plant operation of an opposed multi-burner coal-water slurry gasification

WANG Fuchen, ZHOU Zhijie, DAI Zhenhua, GONG Xin, YU Guangsuo, LIU Haifeng, WANG Yifei, YU Zunhong

《能源前沿（英文）》 2007年 第1卷 第3期   页码 251-258 doi: 10.1007/s11708-007-0035-5

摘要： The features of the opposed multi-burner (OMB) gasification technology, the method and process of the research, and the operation results of a pilot plant and demonstration plants have been introduced. The operation results of the demonstration plants show that when Beisu coal was used as feedstock, the OMB CWS gasification process at Yankuang Cathy Coal Co. Ltd had a higher carbon conversion of 3%, a lower specific oxygen consumption of about 8%, and a lower specific carbon consumption of 2%–3% than that of Texaco CWS gasification at the Lunan Fertilizer Plant. When Shenfu coal was used as feedstock, the OMB CWS gasification process at Hua-lu Heng-sheng Chemical Co. Ltd had a higher carbon conversion of more than 3%, a lower specific oxygen consumption of about 2%, and a lower specific coal consumption of about 8% than that of the Texaco CWS gasification process at Shanghai Coking & Chemical Corporation. The OMB CWS gasification technology is proven by industrial experience to have a high product yield, low oxygen and coal consumption and robust and safe operation.
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医院中子照射器I型堆热中子束流孔道等效平面源的模拟计算

朱养妮,江新标,赵柱民,张良,周永茂

《中国工程科学》 2012年 第14卷 第8期   页码 56-59

摘要：

采用蒙特卡罗程序MCNP模拟计算了医院中子照射器I型堆（IHNI-1）热中子束流孔道出口处的等效平面源。对B堆芯进行了临界搜索计算，模拟计算了热中子束流孔道及出口处中子、γ的束流参数，应用等效平面源模型建立了BNCT等效中子、γ平面源。为人体头颅等效模型剂量分布的快速计算提供了较为可靠的平面源。

关键词： 医院中子照射器I型堆     热中子束流孔道     等效中子平面源     等效γ平面源    

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我国快堆技术发展的现状和前景

徐銤

《中国工程科学》 2008年 第10卷 第1期   页码 70-76

摘要：

考虑到人口众多，经济快速发展，人民生活水平不断提高，人均能源相对贫乏和环境保护，国家已决策加快核能应用的发展。采用压水堆－快堆匹配闭式燃料循环达到核能供应的快速增长和可持续性的基本战略已经决定，也决定了分离和用快堆和ADS对高放废物（MA）的嬗变战略。笔者建议快堆工程发展将分三步进行，中国实验快堆（CEFR，65 MWt/20 MWe），中国原型/示范快堆（CEFR／CDFR,大于等于1 500 MWt/600 MWe）和中国经济验证性快增殖堆（CDFBR,1 000 MWt/1 500 MWe）。CPFR的设计研究已于2006年开始目前正处于安装、调试阶段，计划2009年首次临界。近期讨论建造比600 MWeCPFR更大功率的堆作为CDFR，以加速快堆商用的步伐。

关键词： 快堆发展战略     增殖堆     燃烧堆     中国实验快堆    

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Effects of hydralazine and valproate on the expression of E-cadherin gene and the invasiveness of QBC

Hong LI, Shaoqin CHEN, Yi SHU, Yongjun CHEN, Ying SU, Xin WANG, Shengquan ZOU

《医学前沿（英文）》 2009年 第3卷 第2期   页码 153-157 doi: 10.1007/s11684-009-0034-5

摘要： To clarify the effect of DNA methylation and histone deacetylase inhibitors on the expression of the E-cadherin gene and the invasiveness of the QBC cells, the QBC cells were separately treated with hydralazine, valproate, or combination of the two drugs. The mRNA expression of E-cadherin was examined with reverse transcription-polymerase chain reaction (RT-PCR), the protein of the gene with Western blotting. The methylation status of the promoter region of the gene was detected with methylation-specific PCR (MSP). The invasiveness of QBC cells was detected with transwell assay. It was found that the promoter region of the E-cadherin gene of QBC cells was hypermethylated. Valproate alone could not contribute to demethylation of the gene, whereas hydralazine could make them to be partly demethylated. However, the methylation status of the gene could be thoroughly reversed by using valproate and hydralazine in combination. What’s more, it was confirmed that the E-cadherin gene of QBC cells could not be transcriptionally reactivated by Valproate alone, whereas hydralazine alone could induce moderate reexpression of the gene. However, using valproate and hydralazine in combination could result in robust reexpression of the E-cadherin gene ( =0.000). Likewise, the invasiveness of the QBC939 cells was sharply decreased by treatment with two drugs in combination and slightly decreased with one drug alone. It could be concluded that the two drugs have synergistic effect on the demethylation and reexpression of the E-cadherin gene of QBC cells, and also on the reduction of the invasiveness of the QBC939 cells.

关键词： DNA methylation inhibitor     histone deacetylase inhibitor     bile duct carcinoma     E-cadherin    

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Influence of nozzle height to width ratio on ignition and NO

Liutao SUN, Yonghong YAN, Rui SUN, Zhengkang PENG, Chunli XING, Jiangquan WU

《能源前沿（英文）》 2021年 第15卷 第2期   页码 431-448 doi: 10.1007/s11708-021-0726-3

摘要： To improve the ignition behavior and to reduce the high NO emissions of blended pulverized fuels (PF) of semicoke (SC), large-scale experiments were conducted in a 300 kW fired furnace at various nozzle settings, i.e., ratios (denoted by / ) of the height of the rectangular burner nozzle to its width of 1.65, 2.32, and 3.22. The combustion tests indicate that the flame stability, ignition performance, and fuel burnout ratio were significantly improved at a nozzle setting of / = 2.32. The smaller / delayed ignition and caused the flame to concentrate excessively on the axis of the furnace, while the larger / easily caused the deflection of the pulverized coal flame, and a high-temperature flame zone emerged close to the furnace wall. NO emissions at the outlet of the primary zone decreased from 447 to 354 mg/m (O = 6%), and the ignition distance decreased from 420 to 246 mm when the / varied from 1.65 to 3.22. Furthermore, the ratio (denoted by / ) of the strong reduction zone area to the combustion reaction zone area was defined experimentally by the CO concentration to evaluate the reduction zone. The / rose monotonously, but its restraining effects on NO formation decreased as / increased. The results suggested that in a test furnace, regulating the nozzle / conditions sharply reduces NO emissions and improves the combustion efficiency of SC blends possessing an appropriate jet rigidity.

关键词： rectangular jet burner     nozzle height to width ratio     ignition characteristics     pyrolyzed semicoke (SC) and bituminous blend     NOx formation    

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characteristics at different coal concentrations in bituminous coal ignition in a tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Yiquan XIE, Lingyan ZENG

《能源前沿（英文）》 2013年 第7卷 第2期   页码 255-262 doi: 10.1007/s11708-013-0255-9

摘要： With the objective of producing a full-scale tiny-oil ignition burner, identical to the burner used in an 800 MWe utility boiler, numerical simulations were performed using Fluent 6.3.26 to study the progress of ignition for four coal concentration settings covering sub-operation conditions prevailing during the experiments performed with the burner. The numerical simulations conformed to the experimental results, demonstrating the suitability of the model used in the calculations. Simulations for a coal concentration of 0.40 kg/kg corresponding to a single burner operating at its rated output were also conducted, which indicated that gas temperatures along the burner centerline were high. As gas flowed to the burner nozzle, the high-temperature region expanded, ensuring a successful pulverized-coal ignition. With increasing coal concentration (0.08–0.40 kg/kg), the gas temperature along the burner centerline and at the first and second combustion chamber exits decreased at the equivalent radial points. At the center of the second combustion chamber exit, the O concentrations were almost depleted for the five coal concentrations, while the CO concentrations peaked.

关键词： numerical simulation     tiny-oil ignition burner     pulverized coal     temperature field    

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Influence of different oil feed rate on bituminous coal ignition in a full-scale tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Xiang ZHANG, Zhichao CHEN

《能源前沿（英文）》 2013年 第7卷 第3期   页码 406-412 doi: 10.1007/s11708-013-0266-6

摘要： To reduce oil consumption during firing-up and partial-load operation, a tiny-oil ignition burner has been recommended. Through reacting-flow experiments performed on a full-scale experimental setup, the influence of different oil flow rates on bituminous coal combustion as well as flow rates without coal feed was analyzed. The ignition burner is identical to that normally used in an 800 MWe utility boiler. Under operating conditions with flow rates of 50, 100, and 150 kg/h, gas temperature distributions were measured in the burner. At the equivalent measuring points at the exits of the first and second combustion chambers, these distributions remained almost unchanged under a constant coal feed rate of 4 t/h. However on the burner centerline, distributions increased slightly with increasing flow rate. Different gas concentrations were measured at the center of the burner exit. For instance, the O concentration at the burner exit varied from 0.01% to 0.31% whereas CO concentrations were more than 10000 ppm. At the same coal feed rate of 4 t/h, burner resistances are 480, 600, and 740 Pa for oil flow rates of 50, 100, and 150 kg/h, respectively.

关键词： ignition     coal     burner     boiler     oil flow rate    

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风包粉系列浓淡煤粉燃烧技术的研究

秦裕琨,李争起,孙锐,陈力哲,孙绍增,朱群益,李瑞扬,高继慧,吴少华

《中国工程科学》 2002年 第4卷 第11期   页码 42-49

摘要：

总结了哈尔滨工业大学15年来对浓淡煤粉燃烧技术的研究成果，阐述了浓淡煤粉燃烧技术的原理及所具有的风包粉流动特点，并通过工业试验验证了风包粉原理。针对我国电站锅炉燃煤的特点，提出了需要解决的5个问题，指出了浓淡燃烧技术的发展方向。

关键词： 锅炉     燃烧器     浓淡燃烧     NOx    

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标题 作者 时间 类型 操作

Exergy-energy analysis of full repowering of a steam power plant

S. NIKBAKHT NASERABAD,K. MOBINI,A. MEHRPANAHI,M. R. ALIGOODARZ

期刊论文

Bile duct injury repair — earlier is not better

null

期刊论文

A giant Müllerian duct cyst in the perineum: a case report

null

期刊论文

Influence of mass air flow ratio on gas-particle flow characteristics of a swirl burner in a 29 MW pulverized

Rong YAN, Zhichao CHEN, Shuo GUAN, Zhengqi LI

期刊论文

Diagnosis and treatment of thyroglossal duct carcinoma: Report of three cases with review of literatures

GAO Yan, CHEN Yan, SUN Zhipeng, GUO Chuanbin, YU Guangyan, ZHAN Yi

期刊论文

Numerical simulation of bituminous coal combustion in a full-scale tiny-oil ignition burner: influence

Zhengqi LI, Chunlong LIU, Xiang ZHANG, Lingyan ZENG, Zhichao CHEN

期刊论文

Strategies of minimally invasive treatment for intrahepatic and extrahepatic bile duct stones

null

期刊论文

Development and demonstration plant operation of an opposed multi-burner coal-water slurry gasification

WANG Fuchen, ZHOU Zhijie, DAI Zhenhua, GONG Xin, YU Guangsuo, LIU Haifeng, WANG Yifei, YU Zunhong

期刊论文

医院中子照射器I型堆热中子束流孔道等效平面源的模拟计算

朱养妮,江新标,赵柱民,张良,周永茂

期刊论文

我国快堆技术发展的现状和前景

徐銤

期刊论文

Effects of hydralazine and valproate on the expression of E-cadherin gene and the invasiveness of QBC

Hong LI, Shaoqin CHEN, Yi SHU, Yongjun CHEN, Ying SU, Xin WANG, Shengquan ZOU

期刊论文

Influence of nozzle height to width ratio on ignition and NO

Liutao SUN, Yonghong YAN, Rui SUN, Zhengkang PENG, Chunli XING, Jiangquan WU

期刊论文

characteristics at different coal concentrations in bituminous coal ignition in a tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Yiquan XIE, Lingyan ZENG

期刊论文

Influence of different oil feed rate on bituminous coal ignition in a full-scale tiny-oil ignition burner

Chunlong LIU, Qunyi ZHU, Zhengqi LI, Qiudong ZONG, Xiang ZHANG, Zhichao CHEN

期刊论文

风包粉系列浓淡煤粉燃烧技术的研究

秦裕琨,李争起,孙锐,陈力哲,孙绍增,朱群益,李瑞扬,高继慧,吴少华

期刊论文