84 research outputs found
Experimental Investigation and Thermodynamic Calculation of Phase Equilibria in Some Cu-based Crystalline/Fe-based Amorphous Composites Systems
非晶态合金材料因其高强度、高硬度和耐腐蚀等优异的物理化学性能,在基础科学和实际应用领域受到广泛的关注。然而,室温脆性的存在使非晶态合金材料的应用受到了限制。为了克服室温脆性,晶态/非晶态复合材料作为一种解决方案进入了科研工作者的视野。最近,利用多元合金体系中的液相两相分离现象制备晶态/非晶态复合材料被认为是一种简洁、有效的方法。为了有目的地利用液相两相分离现象制备晶态/非晶态复合材料,就需要建立多元合金体系的热力学数据库,进行材料成分设计。本研究作为Cu基晶态/非晶态复合材料的热力学数据库的重要组成部分,对Fe-Ta-X(X=Cu,Zr)和Cu-B-X(X=Si,Zr)各三元系的相图进行了实验...Amorphous alloys have become a very active field owing to their high strength, good hardness and high corrosion resistance. However, the application of amorphous alloys has been limited as a result of the room-temperature brittleness. Recently, the crystalline/amorphous composites induced by liquid phase separation have been designed and produced in order to solve the room-temperature brittl...学位:工学硕士院系专业:材料学院_材料学学号:2072012115003
拟穴青蟹抗菌肽Crustin新变体的表达特性与抗菌功能
Crustins是一类较早发现并广泛分布在甲壳动物中且富含半胱氨酸的阳离子抗菌肽,能够参与抗细菌的免疫应答。从拟穴青蟹(Scylla paramamosain)中克隆获得Crustin基因,命名为SpCrus1a,其cDNA序列全长744 bp,开放阅读框编码113个氨基酸,成熟肽分子量10.03 kDa,等电点8.30。表达分析结果发现其转录本主要存在于鳃、卵巢、上皮组织中,脂多糖刺激后SpCrus1a会上调表达。体外合成SpCrus1a的第29~47位氨基酸进行抗菌活性实验发现,其对革兰氏阳性菌具有较强的抗菌活性,对被测的革兰氏阴性菌抗菌活性较弱或无抗菌活性。合成肽Sp Crus1a29-47能够在较短时间内杀死绝大多数的金黄色葡萄球菌,2 h内杀死全部的金黄色葡萄球菌。扫描电镜发现合成肽Sp Crus1a29-47可造成金黄色葡萄球菌表面结构崎岖不平,高浓度Sp Crus1a29-47造成细菌的大量死亡。上述结果表明,SpCrus1a是抗菌肽Crustins的新变体。国家自然科学基金(U205123,31172438);;厦门南方海洋研究中心科技项目(14PYY050SF03
Numerical modeling and biomechanical analysis of the human mitral valve
目的建立人体心脏二尖瓣仿真模型,模拟二尖瓣闭合的工作过程,分析二尖瓣各组件应力分布,探讨二尖瓣瓣叶和腱索的相互作用,并探寻腱索受力大小与腱索粗细之间的相关性。方法构建二尖瓣几何模型,在此基础上定义模型单元类型、材料属性、接触、载荷及约束,建立有限元模型,计算模型的应力、速度和位移等参数。结果瓣膜上的应力分布不均匀,后瓣叶亚区之间的裂口位置所受应力最大;不考虑腱索连接至瓣叶时,瓣叶负载后外翻至心房一侧;考虑腱索连接至瓣叶时,前、后瓣叶关闭良好;各腱索受力不同,与前瓣叶相连的支持腱索受力最大,腱索受力大小与腱索粗细之间的线性相关系数为0.954。结论瓣叶中心和后瓣叶亚区之间的裂口两处应力较大区域是临床上二尖瓣裂的常发生部位;与瓣叶相连的腱索可在瓣叶负载时,施加牵拉力使瓣叶不致发生翻转,前、后瓣叶恰好关闭;解剖结构粗壮的腱索受力较大。Objective To establish a numerical model of human mitral valve and simulate its closing process,so as to analyze stress distributions on the valve apparatuses,study the interaction between leaflets of mitral valve and chordae tendineae,and explore the relationship between the force of chordae tendineae and their thickness.Methods A geometric model of human mitral valve was constructed.On the basis of the geometric model,the finite element model was established by defining the element type,material attributes,contacts,loads and constraints.Parameters such as stress,velocity and displacement were calculated after solving the model.Results The stress distribution on the valve was non-uniform.The clefts between the scallops in the posterior leaflet were always under the highest load.When no chordae tendineae were attached,the leaflets turned over to the side of the atrium.When chordea tendineae were attached,the anterior and posterior leaflet could close up successfully.Different chordae tendineae applied different forces to the valve.The strut chorea tendineae attached to the anterior leaflet applied highest force among all the chordea tendineae.The correlation coefficient between the thickness of chordae tendineae and their force was 0.954.Conclusions The two zones with higher stresses,namely the center of the leaflet and the clefts between the three scallops in the posterior leaflet,are also the positions of mitral valve cleft in clinic.Chordea tendineae can apply the pulling force on the leaflets while the mitral valve is under load,thus the leaflets won't turn over to the side of atrium and the valve can close up in time.Chordea tendineae with thicker anatomic structure always apply a higher force on the leaflets.国家自然科学基金资助项目(61102137); 福建省自然科学基金资助项目(2011J01366); 福建省创新医学科研基金(2009-CXB-59
光声/超声双模态成像技术在生物医学中的新进展
随着激光技术、计算机技术与图像处理分析技术的飞速发展,单一模态的医学影像技术正向一体化、多模态及跨尺度影像技术进行革命性转变。多模态影像技术不仅可以实现对同一生物体进行多角度、多参数及分子层面的结构与功能综合特征信息的提取,而且可以弥补单一模式存在的局限性与不足,从而提高疾病早期检测的准确性,为患者提供更加经济合理、精准有效的诊疗方案,对提高人们的生活质量具有非常重要的临床意义。本文重点阐述目前光声/超声双模态成像技术在生物医学以及脑相关疾病中的应用及新进展,系统讨论了该双模态融合技术在未来生物医学领域中的发展前景。国家自然科学青年基金(81701743);;厦门市产学研科技合作项目(3502Z20183018
Research on Salt Tolerance of Rice Transformed by mangrin Gene
以转MAngrIn基因水稻的阳性植株(11#,59#,86#)和阴性植株为材料,在0,100,150,200 MMOl/l的nACl溶液中经盐胁迫7 d后,测定叶片相对含水量、质膜透性、超氧化物歧化酶(SOd)活性和脯氨酸含量4项耐盐指标。结果表明:盐胁迫下,转基因植株的叶片相对含水量、脯氨酸含量、SOd活性明显高于阴性植株,叶片电导率则低于阴性植株。对转基因植株和阴性植株的耐盐性综合评定结果是11#>59#>86#>阴性植株。Plants transformed by mangrin gene(11#,59#,86#) and negatives were tested using several salt tolerance indices,including related water content,cell membrane permeability,SOD activity and proline content,which were conducted under the NaCl concentration of 0,100,150,200 mmol/L after 7 days.The results indicated that the transgenic rice plants accumulated more RWC,proline content and SOD activity than ck under salt stress conditions,yet cell membrane permeability decreased less than ck.According to physiological target in synthetically evaluation,the result is 11#> 59#> 86#> Negatives.福建省青年人才基金项目(2006F3022);福建省自然科学基金项目(2007J0250
Research on the Evolution & Innovation for Modular Product Family
针对当前产品族动态演进机制和系统化创新方法研究的不足,提出模块化产品族在技术层次上的创新演进方法。通过构建产品族的需求—功能—技术(rEQuIrEMEnT-funCTIOn-TECHnOlOgy,r-f-T)映射关系模型,分析当前模块化产品族的技术状况,并通过gM(1,1)模型预测模块化产品族的未来技术重要度情况;在企业内部数据的支持下,通过对模块化产品族初始问题的分析,集成应用创新思维通用理论和传统TrIz(OTSM–TrIz)的问题流网络(PrOblEM flOW nETWOrk,Pfn)技术识别并解决产品族中多个冲突问题;在技术重要度预测和新功能模块—技术关联矩阵(funCTIOn MOdulE-TECHnICAl MATrIX,fMTM)的基础上,以平台比率为依据,通过计算概念化产品族中功能模块的多样性程度,获得概念化产品族规划方案。对小型轮式装载机产品族进行了实例分析,并验证了该方法的有效性。Focusing on the shortage of dynamic evolutionary mechanism and systematic innovation methods of current product family,an innovative and evolutional method at the technical level of modular product family is put forward.The current technical condition of the modular product family is analyzed by constructing requirement-function-technology(R-F-T) mapping model of product family,and the importance of future technology of modular product family is predicted by GM(1,1) model.The multiple conflicts of product family is identified and resolved using PFN technology in the OTSM –TRIZ process,through the analysis of the initial problem of modular product family in support of enterprise data.Moreover,based on prediction of technology importance and the new function module-technical matrix(FMTM),the conceptual planning of product family is obtained by calculating the diversity of function modules of conceptual product family according to platform ratio.An analysis example of product family of small wheel loader show the effectiveness of the method.国家自然科学基金(70772093;71172055);科技部创新方法工作专项(2011M020400);国家科技支撑计划(2011BAF11B00-01);福建省科技重大(2011H6024)资助项
Application of the three-dimensional visualization and 3D printing technology for the preoperative evaluation of retroperitoneal tumors
目的探讨三维重建及3D打印技术在腹膜后肿瘤术前评估中的应用价值。方法回顾性分析2011年3月至2015年9月厦门大学附属成功医院收治的50例腹膜; 后肿瘤病人的临床资料,应用人体器官三维建模软件将病人的CT二维图像重建成三维可视化图像,使用人体器官模型3D打印设备,用两色热塑性塑料打印实物模; 型,通过观察肿瘤与腹腔器官、腹部大血管之间的关系进行术前评估并制定手术方案。实施手术,术中比较重建结果与实际的区别。结果50例病人均成功完成三维; 重建,其中10例病人完成3D打印,三维重建结果及3D打印模型能够立体、清晰和实物化的显示肿瘤解剖学位置及与周围器官、血管的毗邻关系,与术中实际情; 况大致相符。50例病人均顺利施行手术,术中无死亡。结论三维重建及3D打印技术能够对腹膜后肿瘤术前进行精准评估,对指导手术具有一定的应用价值。Objective To explore the application value of three dimensional; visualization and 3D printing technology in the preoperative evaluation; of retroperitoneal tumors. Methods March 2011 to September 2015,the; clinical data of 50 cases of retroperitoneal tumor patients in Xiamen; University Affiliated successful hospital were retrospectively analyzed.; Xiamen strong science and technology R & D human organ 3D modeling; software will reconstruct 2D CT image visualization into a; three-dimensional visualization image,and then it can print physical; model with the company's XMQB-I human organ model 3D printing equipment; and white thermoplastic. At last,preoperative evaluation and surgical; plan can be made through the relationship between the tumor,organs in; abdominal cavity,and abdominal vascular. During the surgery,make a; comparison between the visualization results with the actual condition.; Results 50 cases of patients were successfully completed the; three-dimensional visualization,including 10 cases of patients; completed. Three-dimensional visualization and 3D printing model can; three-dimensionally,clearly show the adjacent relationship between the; anatomical tumour location and surrounding organs and blood; vessels,broadly in line with the actual surgery. 50 surgeries were; successfully performed,no death during perioperative period. Conclusion; Three dimensional visualization and 3D printing technology can make an; accurate preoperative evaluation of retroperitoneal tumors,which has a; certain application value for guiding surgery.国家自然科学基
结肠癌伴孤立巨大肝转移切除术一例
患者男,72岁,因“反复中上腹胀痛不适1月余“入院;既往有乙肝病史,无高血压、糖尿病、心脏病等病史,无手术史。入院查CT示:左肝巨大占位,约22.1 CMx11.3 CM,与胃小弯粘连(图1);门静脉右支无显示(图2),左结肠壁增厚,考虑结肠癌肝转移可能。肿瘤标记物检查示:CEA 54.52μg/l,CA19-9 120.10 u/Ml,AfP正常,血常规、血液生化分析未见国家自然科学基金资助项目(81272246、81101502、61271336、61327001
NMR and Theoretical Study on Interactions between Diperoxovanadate Complex and Substituted Pyridines
为探讨有机配体上取代基团对反应平衡的影响,在模拟生理条件下(0.15mol/L NaCl溶液),应用多核(1H,13C和51V)多维(DOSY)以及变温NMR技术研究双过氧钒配合物[OV(O2)2(D2O)]-/[OV(O2)2(HOD)]-(简写为bpV)与取代吡啶的相互作用.bpV与有机配体的反应性从强到弱的顺序为:皮考林酸根>异烟酸根>异烟酸甲酯>皮考林甲酯,这说明吡啶环上同一位置上的不同取代基团和同一取代基团在不同位置上都影响反应平衡,竞争配位导致一系列新的6配位(配体为异烟酸根和异烟酸甲酯)或7配位(配体为皮考林酸根和皮考林甲酯)的过氧钒物种[OV(O2)2L]n-(L=取代吡啶,n=1或2)生成,密度泛函计算结果较合理地解释了实验结果,并表明溶剂化在反应中起重要作用.To understand the substitution group effects of organic ligands on the reaction equilibrium,the interactions between diperoxovanadate complex [OV(O2)2(D2O)]-/[OV(O2)2(HOD)]-(abbr. bpV) and a series of substituted pyridines were explored using multinuclear(1H,13C,and 51V) magnetic resonance,DOSY,and variable temperature NMR in 0.15 mol/L NaCl ionic medium for mimicking the physiological condition. The reactivity order among the substituted pyridines and bpV is picolinate>isonicotinate> methyl isonicotinate>methyl picolinate. The competitive coordination results in the formation of a series of new six-coordinated(isonicotinate and methyl isonicotinate) or seven-coordinated(picolinate and methyl picolinate) peroxovanadate species [OV(O2)2L]n-(L=substituted pyridines,n=1 or 2). Both the different substitution groups at the same position and the same groups at the different substitution position affect these reactions. The results of density functional calculations provide someway a reasonable explanation for the relative reactivity of the substituted pyridines. Solvation effects play an important role in these reactions.国家自然科学基金(Nos.20772027,20803020);; 973子课题(No.2003CB716005);; 湖南省自然科学基金(No.06JJ30004);; 中国博士后科学基金(No.20070410805);; 湖南省教育厅青年项目(No.06B028);; 固体表面物理化学国家重点实验室资助项目;; 湖南科技大学博士基金(No.E-55107)资助项目
Application of a three-dimensional visualization technology for precise before retroperitoneal tumor surgery(Report of 15 cases)
目的探讨三维可视化技术在腹膜后肿瘤术前评估中的应用价值。方法回顾性分析2011年3月至2013年12月厦门大学附属成功医院收治的15例腹膜后肿瘤病人的临床资料,应用三维可视化技术将病人术前二维CT图像进行三维可视化重建,通过观察肿瘤与腹腔脏器、腹部大血管之间的关系及测量肿瘤体积、手术模拟进行术前评估。对实施手术的病人,比较重建结果与实际手术的区别,对模拟切除肿瘤体积与实际切除肿瘤体积进行相关性分析。结果 15例病人三维可视化重建后图像清晰立体地显示肿瘤组织、腹腔实质脏器、腹腔大血管的解剖结构及毗邻关系,12例评估后行腹膜后肿瘤切除术,三维重建肿瘤的解剖关系与术中大致相符。12例手术病人术前模拟切除肿瘤体积(1117.50±690.35)M l,实际切除肿瘤体积(1189.92±737.74)M l,两者比较差异无统计学意义(T=0.25,P>0.05),具有相关性(r=0.81,P0.05).The actual liver resection volume was positively correlated with the predicted liver resection volume(r=0.81, P<0.05).Conclusions The three-dimensional visualization technology has acertain degree of clinical value in the precise before retroperitoneal tumor surgery.国家自然科学基金资助(No.81272246;81101502;61271336;61327001
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