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Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring 被引量:1
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作者 Chang Rong NIU Hai Ning ZHANG Cheng Tai WU(Department of Chemistry, Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期569-572,共4页
A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines.... A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines. The chemical structures of the new compounds were characterized by elemental analysis, infrared spectra, nuclear magnetic resonance spectra and mass spectrometry. 展开更多
关键词 OCH IR CM KBR HNMR Synthesis of Schiff Base type Macrocycles Containing Naphthalene ring
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Gastric adenocarcinoma of fundic gland type with signet-ring cell carcinoma component: A case report and review of the literature 被引量:20
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作者 Keita Kai Masaaki Satake Osamu Tokunaga 《World Journal of Gastroenterology》 SCIE CAS 2018年第26期2915-2920,共6页
A depressed lesion was found at a gastric angle of 76-yearold Japanese woman by esophagogastroduodenoscopy. Four years prior, she was diagnosed with a Helicobacter pylori infection but no eradication was performed. Th... A depressed lesion was found at a gastric angle of 76-yearold Japanese woman by esophagogastroduodenoscopy. Four years prior, she was diagnosed with a Helicobacter pylori infection but no eradication was performed. The pathological diagnosis of biopsy specimens was signet-ring cell carcinoma. Endoscopic submucosal dissection(ESD) was performed. Histopathological examination of the ESD specimen revealed proliferation of well-differentiated tubular adenocarcinoma mimicking fundic gland cells at the deep layer of the lamina propria mucosae. These tumor cells expressed focally pepsinogen-Ⅰ, diffusely MUC6, and scattered H^+/K^+ ATPase according to immunohistochemistry. Therefore, we diagnosed this tumor as gastric adenocarcinoma of fundic gland type(GA-FG). Adjacent to the GA-FG, proliferation of signet-ring cell carcinoma which diffusely expressed MUC 2 and MUC 5AC was observed. Intestinal metaplasia was focally observed in the surrounding mucosa of the signet-ring cell carcinoma. To the best of our knowledge, this is the first case report of GA-FG with a signet-ring cell carcinoma component. The origin of signet-ring cell carcinoma, i.e., whether it accidentally arose from a non-neoplastic mucosa and coexisted with the GA-FG or dedifferentiated from the GA-FG is unclear at present. We expect the accumulation of similar cases and further analysis to clarify this issue. 展开更多
关键词 Gastric adenocarcinoma of fundic GLAND type Endoscopic SUBMUCOSAL dissection HELICOBACTER PYLORI Intestinal METAPLASIA Signet-ring cell carcinoma
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EFFICIENCY ANALYSIS OF DOUBLE CRANK RING-PLATE-TYPE PIN-CYCLOIDAL GEAR PLANETARY DRIVE 被引量:5
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作者 LiXin HeWeidong +1 位作者 LindaSchmidt LiLixing 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第3期252-255,共4页
From the general formula for calculating the efficiency of planetary geartrains, the efficiency of the double crank ring-plate-type pin-cycloidal gear planetary drive isderived. To prove the theory, an experimental st... From the general formula for calculating the efficiency of planetary geartrains, the efficiency of the double crank ring-plate-type pin-cycloidal gear planetary drive isderived. To prove the theory, an experimental study has been conducted. The tested value of theefficiency of a sample set of the new-type drive in the experiment agrees with the calculated one.It shows that the new-type drive is of not merely high bearing capacity, but also quite highefficiency. 展开更多
关键词 Double crank ring-plate-type Pin-cycloidal gear planetary drive Meshefficiency
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A Novel Design and Fabrication of Magnetic Random Access Memory Based on Nano-ring-type Magnetic Tunnel Junctions 被引量:5
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作者 X.F.Han H.X.Wei Z.L.Peng H.D.Yang J.F.Feng G.X.Du Z.B.Sun L.X.Jiang Q.H.Qin M.Ma Y.Wang Z.C.Wen D.P.Liu W.S.Zhan State 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2007年第3期304-306,共3页
Nano-ring-type magnetic tunnel junctions (NR-MTJs) with the layer structure of Ta(5)/Ir22Mn78(10)/ Co75Fe25(2)/Ru(0.75)/CoooFe20B20(3)/Al(0.6)-oxide/Co60Fe20B20(2.5)/Ta(3)/Ru(5) (thickness unit:... Nano-ring-type magnetic tunnel junctions (NR-MTJs) with the layer structure of Ta(5)/Ir22Mn78(10)/ Co75Fe25(2)/Ru(0.75)/CoooFe20B20(3)/Al(0.6)-oxide/Co60Fe20B20(2.5)/Ta(3)/Ru(5) (thickness unit: nm) were nano-fabricated on the Si(100)/SiO2 substrate using magnetron sputtering deposition combined with the optical lithography, electron beam lithography (EBL) and Ar ion-beam etching techniques. The smaller NR-MTJs with the inner- and outer-diameter of around 50 and 100 nm and also their corresponding NR-MTJ arrays were nano-patterned. The tunnelling magnetoresistance (TMR & R) versus driving current (I) loops for a spin-polarized current switching were measured, and the TMR ratio of around 35% at room temperature were observed. The critical values of switching current for the free Co60Fe20B20 layer relative to the reference Co6oFe2oB2o layer between parallel and anti-parallel magnetization states were between 0.50 and 0.75 mA in such NR-MTJs. It is suggested that the applicable MRAM fabrication with the density and capacity higher than 256 Mbit/inch2 even 6 Gbite/inch2 are possible using both I NR-MTJ+1 transistor structure and current switching mechanism based on based on our fabricated 4×4 MRAM demo devices. 展开更多
关键词 Nano-ring-type magnetic tunnel junctions NR-MTJ MRAM spin polarization Spin transfer effect
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A ring type standing wave ultrasonic motor using cantilever type longitudinal transducers
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作者 刘英想 刘军考 +1 位作者 陈维山 石胜君 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第1期52-56,共5页
The disadvantages of classic ring type ultrasonic motor were analyzed.To obtain large mechanical output power,a ring type standing wave ultrasonic motor using cantilever type longitudinal transducers was proposed.Ther... The disadvantages of classic ring type ultrasonic motor were analyzed.To obtain large mechanical output power,a ring type standing wave ultrasonic motor using cantilever type longitudinal transducers was proposed.There are four pairs of cantilevers on one side of the ring,and four PZT ceramics are set between each pair of cantilevers.A screw fastened the PZT ceramics and cantilevers together to form a longitudinal transducer.The bending vibration mode of the ring is excited by the stretching vibration of the PZT ceramics.Thus,linear simple harmonic motions are achieved at the particle on the teeth.And the driving force is the frictional force between rotor and stator.The working principle of the proposed motor was analyzed.The ring and the longitudinal transducer were designed with FEM.The sensitive parameters of resonant frequency of the transducer and ring could be gained with modal analysis.The longitudinal vibration modal of transducer and bending vibration modal of ring were degenerated,and the motion trajectories of nodes on the teeth were analyzed.The results of this paper could guide the development of this new type of motor. 展开更多
关键词 ultrasonic motor standing wave ring type vibration characteristic FEM
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Presentation of signet ring cell type at carcinoma ventriculi of the patient aged 20 years old
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作者 Afrim Avdaj Ugur Gozalan +3 位作者 Nexhmi Hyseni Hatim Baxhaku Sherif Krasniqi Shpejtim Rramanaj 《Case Reports in Clinical Medicine》 2013年第6期358-362,共5页
Introduction: Diffuse variant of GC is composed of gastric-type mucous cells, which generally do not form glands, but rather permit the mucosa and wall as scattered individual cells or small clusters in an “infiltrat... Introduction: Diffuse variant of GC is composed of gastric-type mucous cells, which generally do not form glands, but rather permit the mucosa and wall as scattered individual cells or small clusters in an “infiltrative” growth pattern. These cells appear to arise from the middle layer of the mucosa, and the presence of intestinal metaplasia is not a prerequisite. In this version, mucin formation expands the malignant cells and pushes the nucleus to the periphery, creating a “signet ring” conformation. If the signetring cells are more than 50% of the tumor, the tumor is classified as signetring cell carcinoma [1]. This case is important for reporting because we encountered for the first time such a carcinoma type, due to the new age and its atypical presentation. Case Presentation: We report a case of a 20 years Albanian old patient with Signet Ring Cell Type of Gastric CA. The patient was brought at the urgency with severe abdominal pain, nausea and peritoneal irritation. Clinical examination has been made in emergency, where we conclude the signs of peritoneal irritation, from native Ro no signs of pneumoperitoneum, while laboratory tests found a slight anemia (erythrocytes 3.36, HCT 25, HGB 8.6). Two hours later we repeated the native RTG and there were present the signs of pneumoperitoneum. It was indicated urgent surgical in-tervention. Intraoperatively, we found Ulcer duodenal perforation and?undertook the operation procedures by Roscoe Graham technique. Conclusions: At this age, it is rare, and it is difficult to detect in its early stages, because the signs and symptoms are often non-existent, non-specific, or mimic as an ulcer. The most common symptoms are early heartburn indigestion, abdominal pain or discomfort, vomiting, constipation, diarrhea or to feel of filling after a small meal, loss of appetite, weakness and fatigue. Less common symptoms are anemia and weight loss. 展开更多
关键词 Signet ring Cell type GASTRIC Adenenocarcinoma DIFFUSE VARIANT of GC
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In-Line Inspection of Pipeline Defects Detection Using Ring-Type Laser 被引量:1
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作者 Mathivanan Durai Yang-Min Hsu Ho Chang 《World Journal of Engineering and Technology》 2021年第3期589-603,共15页
Pipeline plays a vital role in transporting fluids like oils, water, and petrochemical substances for longer distances. Based on the materials they carry</span><span style="white-space:normal;font-size:1... Pipeline plays a vital role in transporting fluids like oils, water, and petrochemical substances for longer distances. Based on the materials they carry</span><span style="white-space:normal;font-size:10pt;font-family:"">,</span><span style="white-space:normal;font-size:10pt;font-family:""> prolonged usage may cause the initiation of defects in the pipeline. These defects occur due to the formed salt deposits, chemical reaction happens between the inner surface and the transferring substance, prevailing environmental conditions, etc. These defects, if not identified earlier may lead to significant losses to the industry. In this work, an in-line inspection system utilizes the nondestructive way for analyzing the internal defects in the petrochemical pipeline. This system consists of a pipeline inspection robot having two major units namely the visual inspection unit and the power carrier unit. The visual inspection unit makes use of a ring-type laser diode and the camera. The laser diode serves as a light source for capturing good quality images of inspection. This unit is controlled by the Arduino in the power carrier unit which provides the necessary movement throughout the pipe. The inspected images captured by the camera are further processed with the aid of NI vision assistant software. After applying the processing function parameters provided by this software, the defect location can be clearly visualized with high precision. Three sets of defects are introduced in a Polylactide (PLA) pipe based on its position and angle along the circumference of the pipe. Further, this robot system serves as a real-time interactive image synchronization system for acquiring the inspected images. By comparing the actual and calculated defect size, the error percentage obtained was less than 5%. 展开更多
关键词 Pipeline Robotic System ring-type Laser Vision Assistant Image Pro-cessing Leak Holes Detection Nondestructive Testing
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Syntheses of Cellulose-Type Polysaccharide by Means of Ring-Opening Copolymerization of Anhydroriboses ABRP and AIRP
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作者 WU Cheng-pei PAN Cai-yuan Toshiyuki Uryu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1998年第2期86-90,共5页
SynthesesofCelulose┐TypePolysaccharidebyMeansofRing┐OpeningCopolymerizationofAnhydroribosesABRPandAIRPWUChen... SynthesesofCelulose┐TypePolysaccharidebyMeansofRing┐OpeningCopolymerizationofAnhydroribosesABRPandAIRPWUCheng-peiandPANCai-yu... 展开更多
关键词 1 4-anhydroribose derivative ringopening copolymerization cellulosetype polysaccharide
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Characterization of a Novel RING-Type Ubiquitin E3 Ligase GhRING2 Differentially Expressed in Cotton Fiber
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作者 Shiva Soma Chuan-Yu Hsu +2 位作者 Sukumar Saha Johnie N. Jenkins Din-Pow Ma 《American Journal of Plant Sciences》 2014年第21期3364-3379,共16页
The ubiquitin-proteasome proteolysis pathway is responsible for the degradation of abnormal and short-lived proteins to regulate many important biochemical activities in eukaryotes. By employing affymetrix microarray ... The ubiquitin-proteasome proteolysis pathway is responsible for the degradation of abnormal and short-lived proteins to regulate many important biochemical activities in eukaryotes. By employing affymetrix microarray analysis, we have identified a novel ubiquitin ligase E3 gene GhRING2 that is differentially expressed between two Gossypium hirsutum lines-Texas Marker-1 (TM-1) and Chromosome Substitution Line CS-B25. The CS-B25 line has chromosome 25 from G. barbadense substituted into TM-1. The complete nucleotide sequences of GhRING2 along with its 5’-flanking region were obtained by genomic walking. GhRING2 was highly expressed in elongating fiber, and GUS expression directed by the GhRING2 promoter was found in hypocotyls and young stems of transgenic Arabidopsis plants. Using a yeast two-hybrid assay GhRING2 was found to interact with a PROTODERMAL FACTOR1 (GhPDF1) protein. GhPDF1 was expressed preferentially in immature ovules and fiber initials, and the GhPDF1 gene had been suggested to play a role in cell fate determination and fiber development. Pull down and plasmid swap assays further confirmed the interaction between GhRING2 and GhPDF1. The expression and protein interaction data indicate that GhRING2 may be involved in the turnover of GhPDF1 and participation in the transition from initiation to elongation stages during fiber development. Our data strongly suggest that the ubiquitin-proteasome pathway may regulate cotton fiber growth and development. The nucleotide sequence data of GhRING2 in this article have been submitted to the Gen Bank Nucleotide Sequence Data Bases under the accession number BankIt 1,742,008 SeqKM 108,000. 展开更多
关键词 Cotton Fiber Gossypium hirsutum G. barbadense ring-type UBIQUITIN LIGASE Ubiquitination
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10kV箱变改造为发电机转子护环感应加热电源的研究与应用
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作者 申雁鹏 王声学 《电气技术》 2024年第4期72-76,共5页
在某核电站汽轮发电机转子首次检修和绕组发生绝缘缺陷时,需要采用感应加热法拆除转子护环进行检查与处理。本文结合电站实际情况及护环拆装需求,经过分析与计算,按照最优的单绕组供电方案将工程建设期退役的10kV箱式变电站改造成拆装... 在某核电站汽轮发电机转子首次检修和绕组发生绝缘缺陷时,需要采用感应加热法拆除转子护环进行检查与处理。本文结合电站实际情况及护环拆装需求,经过分析与计算,按照最优的单绕组供电方案将工程建设期退役的10kV箱式变电站改造成拆装发电机转子护环所需的感应加热电源,并在两台百万千瓦级汽轮发电机的首次大修和转子绝缘缺陷处理中实现成功应用,有效保障了核电站发电机大修工期,节约了大修成本。 展开更多
关键词 箱式变电站 发电机 护环 感应加热
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拟南芥中RING型E3泛素连接酶基因AtGW2的克隆和功能分析 被引量:11
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作者 姜颖 曹言勇 +3 位作者 路运才 唐保军 王利锋 李会勇 《植物遗传资源学报》 CAS CSCD 北大核心 2011年第3期448-454,共7页
水稻R ING型E3泛素连接酶基因O sGW2在调控水稻产量性状方面起着十分重要的作用。根据O sGW2的cDNA序列,通过RT-PCR方法从拟南芥中克隆了一个与O sGW2同源的基因,命名为AtGW2。序列分析表明,该基因编码一个R ING-C2型E3泛素连接酶蛋白,... 水稻R ING型E3泛素连接酶基因O sGW2在调控水稻产量性状方面起着十分重要的作用。根据O sGW2的cDNA序列,通过RT-PCR方法从拟南芥中克隆了一个与O sGW2同源的基因,命名为AtGW2。序列分析表明,该基因编码一个R ING-C2型E3泛素连接酶蛋白,含有401个氨基酸。通过构建AtGW2RNA干扰植物表达载体并转化拟南芥,结果表明,获得的转基因后代植株的子粒较野生型大,并且转基因拟南芥子粒千粒重高于野生型,这表明AtGW2负调控拟南芥子粒大小及粒重。 展开更多
关键词 拟南芥 AtGW2 ring型E3泛素连接酶 RNAI 粒重
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C_(6)H自由基B^(2)Π-X^(2)Π的O_(0)^(0)带光谱的Λ型双重分裂和寿命展宽
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作者 肖增军 顾洁琼 +4 位作者 李振振 储旺友 张强 陈旸 赵东锋 《Chinese Journal of Chemical Physics》 SCIE EI CAS CSCD 2024年第1期19-23,I0117,共6页
本文利用狭缝超声射流等离子体结合高灵敏腔衰荡光谱在18990 cm^(-1)附近研究了C6H碳链自由基B^(2)Π-X^(2)Π电子跃迀000带谱带的高分辨光谱.通过采用一套自研的窄线宽纳秒脉冲激光光源,首次在实验上观测到了该电子跃迁谱带的A型转动... 本文利用狭缝超声射流等离子体结合高灵敏腔衰荡光谱在18990 cm^(-1)附近研究了C6H碳链自由基B^(2)Π-X^(2)Π电子跃迀000带谱带的高分辨光谱.通过采用一套自研的窄线宽纳秒脉冲激光光源,首次在实验上观测到了该电子跃迁谱带的A型转动线分裂,获得了B^(2)Π态精确的A型双重分裂光谱常数p’=-1.16(9)×10^(-3)cm^(-1)和q’=-1.22(7)×10^(-4)cm^(-1),并更精确地确定了考虑A型分裂后修正的B、D、γ等光谱常数.基于谱线线形展宽,获得了B^(2)Π的能级寿命~100±20 ps,并分析了其可能的来源机理. 展开更多
关键词 碳链自由基 腔衰荡光谱 A型双重分裂 寿命展宽
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力载荷下分瓣式碳环密封结构变形研究
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作者 李璐 丁雪兴 +3 位作者 王蕊霞 徐洁 洪先志 包鑫 《润滑与密封》 CAS CSCD 北大核心 2024年第6期57-64,共8页
为探究力载荷下分瓣式碳环密封结构参数对密封面径向变形的影响规律,采用数值计算求解压力控制雷诺方程,获得气膜压力,再结合有限元分析软件进行流固热耦合仿真模拟,探究特定工况下不同结构参数对碳环变形的影响,分析主密封面径向变形... 为探究力载荷下分瓣式碳环密封结构参数对密封面径向变形的影响规律,采用数值计算求解压力控制雷诺方程,获得气膜压力,再结合有限元分析软件进行流固热耦合仿真模拟,探究特定工况下不同结构参数对碳环变形的影响,分析主密封面径向变形特性。研究表明:力变形中,防转销的安装位置对碳环径向变形量影响最大,选取恰当的安装位置可减小径向变形量;外部凸结构不均匀且圆心角比例较大时,径向变形量较小;两侧搭接口比例越大时径向变形量越小;拉紧弹簧和压紧弹簧的选取对碳环径向变形量影响较小;弹簧压力越大时径向变形量越小,但弹簧压力过大时,容易导致碳环磨损加剧、断裂甚至密封失效,应参考实际工况选择适当弹簧压力。研究结果为分瓣式碳环密封的结构优化设计提供参考。 展开更多
关键词 分瓣式碳环 碳环密封 流固耦合 力变形
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TC4合金斜Ⅰ型截面环件轧制工艺研究
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作者 叶宁 王龙祥 +2 位作者 王建国 徐东 宋宝玉 《精密成形工程》 北大核心 2024年第6期77-83,共7页
目的提升钛合金异型环轧制时的填充效果,提高成形精度,确定轧制型腔对环件成形质量的影响。方法以TC4合金斜I型截面环件为研究对象,设计了开式与闭式2种轧制型腔,对该环件的轧制过程进行了研究。建立了斜I型截面环件的有限元模型,基于... 目的提升钛合金异型环轧制时的填充效果,提高成形精度,确定轧制型腔对环件成形质量的影响。方法以TC4合金斜I型截面环件为研究对象,设计了开式与闭式2种轧制型腔,对该环件的轧制过程进行了研究。建立了斜I型截面环件的有限元模型,基于有限元模拟结果全面分析了不同轧制型腔对环件等效应变、温度分布以及型腔填充效果的影响规律。结果与开式型腔相比,闭式型腔轧制的环件具有更优的等效应变和温度分布,型腔填充情况也明显更优,填充率在96%以上,进而确定了闭式型腔的轧制方式。采用设计的闭式型腔进行了环件轧制试验,试验环件尺寸与模拟结果吻合良好,误差在0.3%以内,同时组织性能均能够满足生产要求。结论选择闭式型腔轧制可以有效提升钛合金异型环轧制时的填充效果,提高成形精度,提升环件成形质量。 展开更多
关键词 TC4合金 异型环件 数值模拟 闭式型腔 环件轧制
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基于Q型非球面的全景环带红外光学系统设计
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作者 刘一帆 周峰 +1 位作者 胡斌 晋利兵 《航天返回与遥感》 CSCD 北大核心 2024年第1期90-98,共9页
全景环带光学系统凭借周视范围实时成像的特点已在超大视场光学领域中得到了广泛应用。传统的全景环带光学系统将折射、反射面集成在一片块状透镜中,光线在其内部进行多次折、反射导致头部单元体积较大,同时红外透镜材料密度大、折射率... 全景环带光学系统凭借周视范围实时成像的特点已在超大视场光学领域中得到了广泛应用。传统的全景环带光学系统将折射、反射面集成在一片块状透镜中,光线在其内部进行多次折、反射导致头部单元体积较大,同时红外透镜材料密度大、折射率温度稳定性差等特点也与光学遥感器轻量化、可靠性高的应用需求相矛盾。文章基于像差理论,讨论了全景环带两反射镜红外光学系统头部单元初始结构设计方法,将Q型(Q-Type多项式)非球面引入全景头部单元增加优化变量,用偏离因子因子k_(RMS)数值表征非球面加工难度,设计了以两反射镜为头部单元的全景环带红外光学系统。该系统在奈奎斯特频率(20线对/mm)处调制传递函数优于0.5;全视场像元(25μm×25μm区域内)能量集中度优于65%,像质评价结果表明其成像品质良好。该设计在缩小系统体积、提高光学设计优化效率方面有很大的改进,满足超大视场实时成像的应用需求。 展开更多
关键词 全景环带光学系统 超大视场 Q型非球面 光学遥感器
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基于本体的三稀矿产知识图谱构建
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作者 冯秋睿 赵汀 刘超 《中国矿业》 北大核心 2024年第4期79-88,共10页
长期以来,我国地质工作者开展了大量的三稀矿产调查研究工作,积累了海量的地质勘查资料,其中蕴含了极为丰富的三稀矿产矿床地质特征、矿床成因、矿床地质环境、构造背景等相关知识。如何集中管理这些数据,并且使用一种形式化的方式进行... 长期以来,我国地质工作者开展了大量的三稀矿产调查研究工作,积累了海量的地质勘查资料,其中蕴含了极为丰富的三稀矿产矿床地质特征、矿床成因、矿床地质环境、构造背景等相关知识。如何集中管理这些数据,并且使用一种形式化的方式进行表达以支持地学知识的计算和推理,成为当前地学人工智能领域的热点问题。本文引入知识工程中知识抽取、知识表示技术,基于三稀矿产有关的非结构化数据,开展知识图谱构建。首先,明确了三稀矿产的概念、实体、关系,建立了三稀矿产的知识体系,并以此建立三稀矿产本体;其次,根据建立的三稀矿产本体使用深度学习的方式抽取知识,建立三稀矿产知识图谱;最后,为了直观表达实体之间的关系,以及矿床本体的属性集合,使用Neo4j图数据库存储三元组,将知识图谱可视化。本文的研究成果可提供三稀矿产科研、管理、三稀矿产知识获取、三稀矿产知识分析、三稀矿产知识可视化等功能,为三稀矿产领域知识图谱构建提供一个应用范例,也为后续基于知识图谱的地学知识推理、识别和管理矿产资源、成矿预测等应用提供支持。 展开更多
关键词 知识图谱 深度学习 三稀矿产 知识工程 知识抽取 人工智能
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铁观音茶树RING型E3泛素连接酶基因克隆及其干旱胁迫下的表达分析 被引量:1
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作者 常笑君 郭玉琼 +4 位作者 王仲 赵姗姗 朱晨 林玉玲 赖钟雄 《福建农业学报》 CAS 北大核心 2016年第8期826-832,共7页
以铁观音茶树为试材,对其中E3泛素连接酶基因进行克隆和生物信息学分析,并采用qPCR进行不同干旱条件下的定量表达分析。研究结果表明,该序列全长为1 138bp,开放阅读框(ORF)为810bp,编码269个氨基酸(GenBank登录号KR819177)。生物信息学... 以铁观音茶树为试材,对其中E3泛素连接酶基因进行克隆和生物信息学分析,并采用qPCR进行不同干旱条件下的定量表达分析。研究结果表明,该序列全长为1 138bp,开放阅读框(ORF)为810bp,编码269个氨基酸(GenBank登录号KR819177)。生物信息学分析发现该铁观音茶树E3泛素连接酶基因不含跨膜结构以及信号肽,具有多个磷酸化位点,亚细胞定位于叶绿体中。经BLAST比对,该基因编码的氨基酸序列与烟草、亚麻荠、葡萄、醉蝶花、芜菁中的E3泛素连接酶基因编码的氨基酸序列分别有51%、50%、50%、50%和49%的同源性,且相关保守功能结构域翻译的蛋白质序列具有RING-finger结构,初步确定该基因为铁观音茶树的E3泛素连接酶基因。qPCR分析结果显示在不同干旱胁迫处理下铁观音茶树的E3泛素连接酶基因的表达量,与对照组相比显著增加。本研究认为铁观音茶树RING型E3泛素连接酶基因参与茶树抗旱响应机制。 展开更多
关键词 铁观音 ring型E3泛素连接酶 基因克隆 干旱胁迫 qPCR
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电动汽车锂电池组双层环形均衡器研究
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作者 韩欣晟 阚加荣 +2 位作者 凌慧颖 王鹏 成乾 《电子科技》 2024年第4期16-24,共9页
传统Buck-Boost均衡电路传输路径长且均衡效率低,现有的环形均衡器无法从根本上解决该问题。针对该问题,文中提出了一种基于Buck-Boost及开关电容的锂电池双层环形均衡器。该均衡电路采用模块化均衡的方法在底层模块和顶层模块采用Buck-... 传统Buck-Boost均衡电路传输路径长且均衡效率低,现有的环形均衡器无法从根本上解决该问题。针对该问题,文中提出了一种基于Buck-Boost及开关电容的锂电池双层环形均衡器。该均衡电路采用模块化均衡的方法在底层模块和顶层模块采用Buck-Boost和开关电容的混合电路实现均衡,并采用图论分析的方法,从均衡速度、均衡效率两方面分析电路结构。结果表明,该均衡电路具有能量传输路径少、能量传输效率高的优点。文中在MATLAB/Simulink电力仿真平台上搭建了均衡电路的仿真模型,仿真结果表明基于Buck-Boost及开关电容的双层环形均衡器比单层环形均衡器均衡速度提高了46%。文中搭建了4节电池的实验样机对环形均衡电路工作原理及系统均衡效率进行实验验证,结果表明双层环形均衡器比单层环形均衡器均衡效率可提高26.78%。仿真与实验结果与理论分析一致,说明电路结构合理有效。 展开更多
关键词 锂电池 环式结构 均衡器 图论法 概率论 双向环式 混合拓扑 双层结构 串联电池组
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C频段的“推扫式”卫星扫描天线
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作者 牛广群 栗曦 李一楠 《空间电子技术》 2024年第2期66-71,共6页
该设计结合科研实际需求,研制了工作在C频段的“推扫式”卫星扫描天线。首先,从“推扫式”卫星扫描天线的原理出发,对所需要的环焦反射面进行了优化建模,提出一种新型扇形反射面圆角化的方案,并针对密集馈源阵进行分析。通过计算得到了... 该设计结合科研实际需求,研制了工作在C频段的“推扫式”卫星扫描天线。首先,从“推扫式”卫星扫描天线的原理出发,对所需要的环焦反射面进行了优化建模,提出一种新型扇形反射面圆角化的方案,并针对密集馈源阵进行分析。通过计算得到了馈源的位置坐标,在仿真软件GRASP中构造反射面天线的整体模型。为了使密集馈源阵的主波束满足设计指标,设计了遗传算法优化合成后的波束来实现对主波束的优化,通过改变馈源阵的幅相值以达到天线方向图的设计要求,利用仿真优化得到了C频段中心波束达到设计指标所需要的馈源阵规模。最后,对整体模型进行了加工组装。使用近场测量的方法在微波暗室中对天线进行测试,测试结果表明天线波束宽度为0.6°时,主波束效率为98.17%,大于98%,满足设计要求。 展开更多
关键词 C频段 推扫式 环焦抛物面
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浙江纺纱产业结构调整与产品升级的几点探索
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作者 杨骞 章友鹤 张毅 《浙江纺织服装职业技术学院学报》 2024年第2期5-11,19,共8页
浙江省是国内重要的纺织工业地区之一,具有100多年纺纱历史。目前国内外市场形势的变化使浙江省以出口为主的纺织产业受到了极大的冲击。根据网络公开2010~2022年全国各省市纱的产量排名,浙江省纱产能被其他省或地区超越,针对浙江纺纱... 浙江省是国内重要的纺织工业地区之一,具有100多年纺纱历史。目前国内外市场形势的变化使浙江省以出口为主的纺织产业受到了极大的冲击。根据网络公开2010~2022年全国各省市纱的产量排名,浙江省纱产能被其他省或地区超越,针对浙江纺纱产业的地位与作用及近几年来被动的原因进行了分析,通过对新型纺纱的技术创新及开发产品范围拓展,指出要重振纺纱产业,必须要加快产业结构调整,淘汰或改造使用年限已久的环锭纺设备,提高设备的全自动化与智能化程度,控制环锭纺纱产能,重点发展新型纺纱,开发市场需求的新型纱线,实现产业转型升级,走减量增值之路,进一步提高在国内外市场的竞争力。 展开更多
关键词 纺织产业 结构调整 纺织产品 环锭纺 新型纺纱
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