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Breeding and Seed Reproduction Techniques of a New Tetraploid Common Buckwheat Variety‘Pintianqiao 3’
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作者 Xinghai SHI Jiandong ZHAO +5 位作者 Xiulian LI Wenliang CHEN Xiuzhen QIN Jun REN Xiaohuan YANG Jinhu MA 《Agricultural Biotechnology》 2024年第3期5-7,13,共4页
[Objectives]This study was conducted to actively carry out the breeding of new tetraploid common buckwheat varieties and its supporting breeding techniques.[Methods]Pintianqiao 3 is a new tetraploid common buckwheat v... [Objectives]This study was conducted to actively carry out the breeding of new tetraploid common buckwheat varieties and its supporting breeding techniques.[Methods]Pintianqiao 3 is a new tetraploid common buckwheat variety developed by College of Agriculture of Shanxi Agricultural University and Agricultural Genetic Resources Center of Shanxi Agricultural University,using‘Pintianqiao 1’as the parent,through mutation treatment with 0.2%colchicine aqueous solution,grain selection,plant selection,isolation and identification,variety comparison,regional test and field investigation.The variety has chromosomes 2n=4X=32,and shows a spring sowing period of 101 d and a summer sowing period of 80 d,large flowers and seeds(with a 1000-grain weight of 41.4 g),and good resistance to lodging.[Results]From 2021 to 2022,Pintianqiao 3 participated in the independent joint regional test of common buckwheat varieties in Shanxi Province,and the average yield in 10 test positions was 1.8 kg,equivalent to 1800 kg/hm^(2),which was 8.4%higher than the control.It passed the field investigation conducted by Shanxi provincial expert group for identification of non-major crop varieties in Dongyang and Kelan experimental sites on September 2-3,2022.On January 4,2024,it passed the preliminary examination of Shanxi Provincial Crop Variety Approval Committee.The seed reproduction technique of Pintianqiao 3 including land selection,preparation before sowing,sowing,field management and timely harvesting has been developed.[Conclusions]This study provides technical support for the demonstration and popularization of this new variety. 展开更多
关键词 TETRAPLOID Pintianqiao 3 BREEDING CHARACTERISTIC Breeding technique
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Assessment of the effects of induced anisometropia on binocularity with glasses-free 3D technique 被引量:1
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作者 Xu-Bo Yang Wei-Dong Huang Yong-Chuan Liao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第4期601-607,共7页
AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in... AIM:To assess the effect of experimentally induced anisometropia on binocularity in normal adults with glassesfree three-dimensional(3D)technique.METHODS:Totally 54 healthy medical students with normal binocularity in the cross-sectional study were enrolled.Anisometropia was induced by placing trail lenses over the right eye,in 0.5 D steps including lenses of-0.5,-1,-1.5,-2,-2.5 D(hyperopic anisometropia)and lenses of+0.5,+1,+1.5,+2,+2.5 D(myopic anisometropia).The glasses-free 3D technique was used to evaluated not only fine stereopsis,but also coarse stereopsis,dynamic stereopsis,foveal suppression,and peripheral suppression in these subjects.One-way analysis of variance was used to compare quantitative data such as fine stereopsis,coarse stereopsis.Pearson’s Chi-square test was performed to compare categorical data such as dynamic stereopsis,foveal suppression and peripheral suppression.RESULTS:The subjects showed a statistically significant decline in fine stereopsis,coarse stereopsis,and dynamic stereopsis with increasing levels of anisometropia(P<0.001).Binocularity was af fected when induced anisometropia was more than 1 D(P<0.05).Foveal suppression and peripheral suppression were evident and increased in proportion to anisometropia(P<0.001).CONCLUSION:The relatively low degrees of anisometropia may have a potentially significant effect on high-grade binocular interaction.The mechanisms underlying the defect of binocularity seem to involve not only foveal suppression,but also peripheral suppression. 展开更多
关键词 ANISOMETROPIA binocularity STEREOPSIS glasses-free 3D technique
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32×32 Si盖革模式激光焦平面探测器
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作者 王江 王鸥 +5 位作者 刘向东 袁利 柯尊贵 郝昕 覃文治 杨赟秀 《激光技术》 CAS CSCD 北大核心 2024年第5期665-670,共6页
为了满足350 nm~1100 nm波长范围内远距离及微弱激光3维成像探测的需求,提出了一种规模为32×32的盖革模式硅激光焦平面阵列探测器,它主要由硅雪崩光电二极管阵列、读出电路芯片、微透镜阵列、半导体制冷器、引脚网格阵列壳体等元... 为了满足350 nm~1100 nm波长范围内远距离及微弱激光3维成像探测的需求,提出了一种规模为32×32的盖革模式硅激光焦平面阵列探测器,它主要由硅雪崩光电二极管阵列、读出电路芯片、微透镜阵列、半导体制冷器、引脚网格阵列壳体等元件组成。硅雪崩光电二极管焦平面阵列采用拉通型N^(+)-Π_(1)-P^(-)-Π_(2)-P^(+)结构,工作在盖革模式下,通过Si片背面抛磨减薄及盲孔刻蚀技术,实现了纤薄光敏区的加工;读出电路采用主动模式淬灭设计,使电路单元的死时间控制在50 ns以内,并利用一种带相移技术的时间数字转换电路优化方案,在满足时间分辨率不大于2 ns的同时,降低了读出电路芯片的功耗。结果表明,在反向过偏电压14 V、工作温度-40℃的条件下,该探测器在850 nm的目标波长可实现20.7%的平均光子探测效率与0.59 kHz的平均暗计数率,时间分辨率为1 ns,有效像元率优于97%。该研究为纤薄型背进光Si基激光焦平面探测器的研制提供了参考。 展开更多
关键词 传感器技术 雪崩焦平面探测器 盖革模式 激光3维成像
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粮草双高型大麦新品种皖饲麦3号的选育及栽培技术
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作者 赵斌 王瑞 +3 位作者 季昌好 孙皓 朱斌 陈晓东 《大麦与谷类科学》 2024年第4期76-79,共4页
皖饲麦3号是安徽省农业科学院作物研究所采用系谱法选育而成的粮草双高型饲用大麦新品种。2018—2020年度参加安徽省多点联合鉴定,平均产量达480.64 kg/667 m^(2),比对照西引二号增产10.42%。2023年通过农业农村部非主要农作物品种登记... 皖饲麦3号是安徽省农业科学院作物研究所采用系谱法选育而成的粮草双高型饲用大麦新品种。2018—2020年度参加安徽省多点联合鉴定,平均产量达480.64 kg/667 m^(2),比对照西引二号增产10.42%。2023年通过农业农村部非主要农作物品种登记,登记号:GPD大麦(青稞)(2023)340003。皖饲麦3号为春性多棱皮大麦,茎秆粗壮,分蘖力较好,生育期187 d左右,株高90 cm左右,千粒质量31 g左右,籽粒蛋白质含量(质量分数,下同)10.31%,淀粉含量632.6 g/kg,β-葡聚糖含量5.01%,综合农艺性状较好,抗倒性强。为充分发挥该品种在安徽省沿淮、江淮地区饲料大麦生产中的作用,系统介绍了其选育过程、特征特性,并提出了以收获青饲草、青贮饲料和籽粒为不同目的的配套高产栽培技术。 展开更多
关键词 粮草双高 大麦 皖饲麦3 品种特性 栽培技术
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3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术应用效果及对血清MMP-9和IGF-1水平的影响
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作者 韩莹 陈兴河 +2 位作者 王永恒 赵锦程 吴磊 《中国医学装备》 2024年第4期112-116,共5页
目的:探究3D打印技术在经鼻蝶窦入路垂体腺瘤(PA)切除术的应用效果及对血清基质金属蛋白酶-9(MMP-9)和胰岛素样生长因子-1(IGF-1)水平的影响。方法:选取2020年5月至2022年5月秦皇岛市第一医院收治的84例PA患者,按照随机数表法将其分为... 目的:探究3D打印技术在经鼻蝶窦入路垂体腺瘤(PA)切除术的应用效果及对血清基质金属蛋白酶-9(MMP-9)和胰岛素样生长因子-1(IGF-1)水平的影响。方法:选取2020年5月至2022年5月秦皇岛市第一医院收治的84例PA患者,按照随机数表法将其分为观察组和对照组,每组42例。对照组行经鼻蝶窦入路垂体腺瘤切除术,观察组行经鼻蝶窦入路垂体腺瘤切除术联合应用3D打印技术,比较两组肿瘤切除效果、围术期指标、视力改善情况、MMP-9和IGF-1水平,以及鼻腔功能的鼻气道阻力(NAR)、T&T嗅觉测试评分及并发症。结果:观察组肿瘤切除效果优于对照组,差异有统计学意义(U=2.286,P<0.05);观察组手术时间、术中出血量及住院时间均少于对照组,差异有统计学意义(t=4.780、11.438、11.842,P<0.05);术后3 d、7 d时观察组血清MMP-9和IGF-1水平低于对照组,差异有统计学意义(F=7.526、4.985,P<0.05);术后1个月、3个月时观察组NAR及T&T嗅觉测试评分低于对照组,差异有统计学意义(F=6.359、8.436,P<0.05);两组视力视野改善情况及并发症发生率比较,差异无统计学意义(P>0.05)。结论:3D打印技术用于经鼻蝶窦入路垂体腺瘤切除术可提高肿瘤切除效果,优化手术操作,减少创伤,有利于减轻疼痛,改善嗅觉功能与视力视野,并能降低血清MMP-9、IGF-1水平,且安全性较高。 展开更多
关键词 垂体腺瘤 经鼻蝶窦入路垂体腺瘤(PA)切除术 3D打印技术 基质金属蛋白酶-9(MMP-9) 胰岛素样生长因子-1(IGF-1)
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3D-STI评价STEMI经皮冠状动脉介入术后左心室收缩功能的变化研究
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作者 王荣荣 《医学理论与实践》 2023年第14期2439-2441,共3页
目的:探讨三维斑点追踪技术(3D-STI)评价急性ST段抬高心肌梗死(STEMI)经皮冠脉介入术(PCI)后患者左心室收缩功能的变化。方法:选取2021年1月—2022年5月医院收治的50例STEMI患者为观察组,选取同期无心肌梗死体检者40例为对照组,均实施了... 目的:探讨三维斑点追踪技术(3D-STI)评价急性ST段抬高心肌梗死(STEMI)经皮冠脉介入术(PCI)后患者左心室收缩功能的变化。方法:选取2021年1月—2022年5月医院收治的50例STEMI患者为观察组,选取同期无心肌梗死体检者40例为对照组,均实施了3D-STI技术诊断,评价患者手术前后及与健康人的左心室收缩功能变化情况。同时观察组患者术后随访12个月,将术后12个月发生心血管不良事件(MACE)患者作为MACE组,比较MACE组与无MACE组患者的左心室收缩功能变化。结果:观察组术前、术后左室射血分数(LVEF)和左心室整体的收缩期纵向峰值应变、径向、圆周以及面积应变(GLS、GRS、GCS、GAS)均低于对照组,左心室收缩末期及舒张末期容积(LVESV、LVEDV)均高于对照组(P<0.05)。左心室重构组患者GLS、GRS、GCS、GAS、LVEF均低于未重构组,MACE组GLS、GRS、GCS、GAS、LVEF均低于无MACE组(P<0.05)。采用Spearman相关性分析,GLS、GCS、GAS与LVEF呈负相关性(P<0.05),GRS与LVEF呈正相关性(P<0.05)。结论:3D-STI能够定量评价STEMI患者PCI术后的左心室收缩功能的变化,为术后疗效评价提供客观依据。 展开更多
关键词 3d-sti STEMI PCI 左心室收缩功能
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MoS_(2)/Si tunnel diodes based on comprehensive transfer technique
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作者 朱翊 吕红亮 +4 位作者 张玉明 贾紫骥 孙佳乐 吕智军 芦宾 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第1期106-112,共7页
Due to the pristine interface of the 2D/3D face-tunneling heterostructure with an ultra-sharp doping profile, the 2D/3D tunneling field-effect transistor(TFET) is considered as one of the most promising low-power devi... Due to the pristine interface of the 2D/3D face-tunneling heterostructure with an ultra-sharp doping profile, the 2D/3D tunneling field-effect transistor(TFET) is considered as one of the most promising low-power devices that can simultaneously obtain low off-state current(IOFF), high on-state current(ION) and steep subthreshold swing(SS). As a key element for the 2D/3D TFET, the intensive exploration of the tunnel diode based on the 2D/3D heterostructure is in urgent need.The transfer technique composed of the exfoliation and the release process is currently the most common approach to fabricating the 2D/3D heterostructures. However, the well-established transfer technique of the 2D materials is still unavailable.Only a small part of the irregular films can usually be obtained by mechanical exfoliation, while the choice of the chemical exfoliation may lead to the contamination of the 2D material films by the ions in the chemical etchants. Moreover, the deformation of the 2D material in the transfer process due to its soft nature also leads to the nonuniformity of the transferred film,which is one of the main reasons for the presence of the wrinkles and the stacks in the transferred film. Thus, the large-scale fabrication of the high-quality 2D/3D tunnel diodes is limited. In this article, a comprehensive transfer technique that can mend up the shortages mentioned above with the aid of the water and the thermal release tape(TRT) is proposed. Based on the method we proposed, the MoS_(2)/Si tunnel diode is experimentally demonstrated and the transferred monolayer MoS_(2) film with the relatively high crystal quality is confirmed by atomic force microscopy(AFM), scanning electron microscopy(SEM), and Raman characterizations. Besides, the prominent negative differential resistance(NDR) effect is observed at room temperature, which verifies the relatively high quality of the MoS_(2)/Si heterojunction. The bilayer MoS_(2)/Si tunnel diode is also experimentally fabricated by repeating the transfer process we proposed, followed by the specific analysis of the electrical characteristics. This study shows the advantages of the transfer technique we proposed and indicates the great application foreground of the fabricated 2D/3D heterostructure for ultralow-power tunneling devices. 展开更多
关键词 2D/3D heterostructure transfer technique tunnel diode MoS_(2)/Si
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La_(2)O_(3)掺杂铁基记忆合金涂层组织与性能研究
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作者 徐娜 庞驰 +2 位作者 徐鹏 王卫 荆志杰 《激光技术》 CAS CSCD 北大核心 2024年第3期387-394,共8页
为了探究La_(2)O_(3)对激光熔覆形状记忆合金涂层组织和性能的影响,采用宽带激光熔覆技术在42CrMo中碳钢表面制备了掺杂La_(2)O_(3)的Fe17Mn5Si10Cr5Ni形状记忆合金复合涂层,通过表征得到了La_(2)O_(3)对复合涂层的显微组织、维氏硬度... 为了探究La_(2)O_(3)对激光熔覆形状记忆合金涂层组织和性能的影响,采用宽带激光熔覆技术在42CrMo中碳钢表面制备了掺杂La_(2)O_(3)的Fe17Mn5Si10Cr5Ni形状记忆合金复合涂层,通过表征得到了La_(2)O_(3)对复合涂层的显微组织、维氏硬度、耐磨性、耐蚀性和表面残余应力的影响结果。结果表明,La_(2)O_(3)显著降低了晶粒尺寸,掺杂质量分数w=0.009时,晶粒尺寸达到最小值3.03μm,而复合涂层具有最大硬度454.7 HV 0.2,磨损量最低;并得到最低的自腐蚀电流为4.287×10^(-7)A/cm^(2),最高的自腐蚀电位为-0.843 V,涂层保护率达到94.83%,La_(2)O_(3)明显提高了涂层的耐腐蚀性能;此时涂层的残余应力由拉应力转变为压应力,并在Fe-Mn-Si/La_(2)O_(3)产生的最大残余压应力值为-378 MPa。此项研究为低应力高性能激光熔覆涂层的开发和推广提供了实践参考。 展开更多
关键词 激光技术 涂层 激光熔覆 La_(2)O_(3) 形状记忆合金
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The Application and Operation-Effect Analysis for Complex Tibial Plateau Fractures with 3D Printing Technique 被引量:3
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作者 Changjin Guo Yubo Zhang +2 位作者 Li Yang Qiaofeng Zhu Sanming Zou 《International Journal of Clinical Medicine》 2019年第3期101-108,共8页
Objective: To investigate the value of 3D printing techniques in the treatment of complex tibial plateau fractures. Methods: From September 2016 to September 2018, 28 patients with complex tibial plateau fractures wer... Objective: To investigate the value of 3D printing techniques in the treatment of complex tibial plateau fractures. Methods: From September 2016 to September 2018, 28 patients with complex tibial plateau fractures were treated in our hospital. According to the odevity of hospitalized order, the patients were divided into two groups. Group A used 3D reconstruction, virtually reduction, 3D printing and demonstration of individual fracture model before operation while group B only received conventional process by use X-rays or CT image. Comparison between the two groups was made in operation time, operative blood loss, radiation frequency, surgery instrument cost and knee function score. Results: The follow-up was 14.4 months on average (ranged 6 to 22 months). There was no statistical difference of the surgery instrument cost between the 2 groups (P > 0.05). The operation time of group A was significantly shorter than that of group B (P χ2 = 0.373, P = 0.54). Conclusion: 3D printing techniques can improve surgery effect in complex tibial plateau fractures. 展开更多
关键词 TIBIAL PLATEAU FRACTURE 3D PRINTING technique Individualized Treatment
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Kinetics and the difference for extraction of praseodymium and neodymium from nitrate aqueous solution by [A336][NO_3] using the single drop technique 被引量:1
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作者 Xiaoqin Wang Kun Huang +3 位作者 Wenjuan Cao Pan Sun Weiyuan Song Huizhou Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2020年第5期1326-1333,共8页
The kinetics and the difference for Pr(Ⅲ)and Nd(Ⅲ)extraction from nitrate aqueous solution using trialkylmethylammonium nitrate([A336][NO3])as extractant were investigated by the single drop technique.The dependence... The kinetics and the difference for Pr(Ⅲ)and Nd(Ⅲ)extraction from nitrate aqueous solution using trialkylmethylammonium nitrate([A336][NO3])as extractant were investigated by the single drop technique.The dependence of the extraction rate of Pr(Ⅲ)and Nd(Ⅲ)on the concentrations of free Pr(Ⅲ)and Nd(Ⅲ)ions,the concentrations of Na NO3 and H+in aqueous solutions,and the concentrations of[A336][NO3]in kerosene solutions were discussed and the corresponding extraction rate equations for Pr(Ⅲ)and Nd(Ⅲ)were obtained.These equations demonstrated that the reaction rate constant of Pr(Ⅲ)with[A336][NO3]was double than that of Nd(Ⅲ).The effect of the addition of diethylenetriaminepentaacetic acid(DTPA)on the difference in the extraction rate of Pr(Ⅲ)and Nd(Ⅲ)by[A336][NO3]was also investigated.It was revealed that the difference in the complex formation rates of Pr(Ⅲ)and Nd(Ⅲ)with DTPA made a significant impact on the difference in the extraction rates of Pr(Ⅲ)and Nd(Ⅲ)with[A336][NO3].The ratio of extraction rates of Pr(Ⅲ)to Nd(Ⅲ)with[A336][NO3]was in proportion to the ratio of complex formation rates of Pr(Ⅲ)to Nd(Ⅲ)with DTPA.The extraction rate difference for Pr(Ⅲ)and Nd(Ⅲ)with[A336][NO3]increased due to a higher complex formation rate constant of DTPA with the free and un-complexed Nd(Ⅲ)ions in the aqueous nitrate solution than that with Pr(Ⅲ)ions.Therefore,the addition of DTPA in the aqueous nitrate solution is an effective method to intensify the separation of Pr(Ⅲ)and Nd(Ⅲ)in kinetics.The study on the extraction mechanism indicated that both the extraction of Pr(Ⅲ)and Nd(Ⅲ)by[A336][NO3]were diffusion controlled,and the reactions obeyed SN2 mechanism.The present work highlights a possible approach to strengthen the kinetic separation of Pr(Ⅲ)and Nd(Ⅲ). 展开更多
关键词 PRASEODYMIUM NEODYMIUM [A336][NO3] KINETICS Single drop technique
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哈尔滨地区“绥李3号”高效栽培技术 被引量:1
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作者 刘争 张莉莉 +3 位作者 马骁 李鹏举 侯帅 周沫 《北方园艺》 CAS 北大核心 2024年第8期148-151,共4页
“绥李3号”是黑龙江省农业科学院浆果研究所选育的优质李鲜食品种,具有果个大、酸甜适口、丰产、品质极佳、适应性强、抗寒等特性。在简单介绍哈尔滨地区李高效栽培技术的基础上,阐述了李树栽培技术,分析了果实结实率、果实产量等相关... “绥李3号”是黑龙江省农业科学院浆果研究所选育的优质李鲜食品种,具有果个大、酸甜适口、丰产、品质极佳、适应性强、抗寒等特性。在简单介绍哈尔滨地区李高效栽培技术的基础上,阐述了李树栽培技术,分析了果实结实率、果实产量等相关性状,提出了哈尔滨地区“绥李3号”水肥一体化高效高产栽培技术。旨在促进李产业的规模化、标准化、产业化生产,为促进李产业提质增效、实现可持续发展提供参考依据。 展开更多
关键词 李树 “绥李3号” 栽培技术
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2-己基癸酸改性的全溶液制备的CsPbBr_(3)量子点发光二极管
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作者 吴加其 王程杨 +1 位作者 陆红波 朱俊 《液晶与显示》 CAS CSCD 北大核心 2024年第7期875-882,共8页
钙钛矿量子点发光二极管是极具发展潜力的新型显示技术。全无机CsPbX3(X=Cl,Br,I)钙钛矿量子点具有优异的光电性能,然而合成CsPbX3量子点时往往需要油酸(OA)和油胺(OAm)等配体的参与,这些配体和量子点之间的动态结合方式使其极易从量子... 钙钛矿量子点发光二极管是极具发展潜力的新型显示技术。全无机CsPbX3(X=Cl,Br,I)钙钛矿量子点具有优异的光电性能,然而合成CsPbX3量子点时往往需要油酸(OA)和油胺(OAm)等配体的参与,这些配体和量子点之间的动态结合方式使其极易从量子点表面脱落,进而引发量子点的不稳定性现象。此外,油酸油胺的绝缘特性会阻碍发光二极管中载流子的传输并恶化器件性能。鉴于此,本文以CsPbBr_(3)量子点为研究对象,采用短链配体2-己基癸酸(DA)部分取代长链OA配体,系统探究了不同DA/OA摩尔比对CsPbBr_(3)量子点光学性能的影响。结果表明,经DA修饰的CsPbBr_(3)量子点表现出高达88.64%的光致发光量子产率。随后,将优化后的CsPbBr_(3)量子点应用到全溶液制备的发光二极管中,器件的最高亮度和最大外量子效率分别从9 cd·m^(-2)和0.04%提升至155 cd·m^(-2)和0.14%。接着,通过优化钙钛矿发光层和空穴传输层之间的能级匹配,进一步将器件的亮度和外量子效率提升至436 cd·m^(-2)和0.20%。 展开更多
关键词 CsPbBr_(3)量子点 新型显示技术 发光二极管 配体取代 全溶液制备
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Permittivity of composites used for Luneburg lens antennas by drilling holes based on 3-D printing technique
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作者 DONG Changsheng CUI Ziqing +3 位作者 LI Yong WANG Haidong JIN Chao YANG Shiwen 《太赫兹科学与电子信息学报》 2017年第4期646-651,共6页
Due to the attractive performances such as the ability of beam focus,broadband,multi-beam scanning and other features,Luneburg lens antennas are applied in multi-beam antenna,which overcomes the problem of gain loss p... Due to the attractive performances such as the ability of beam focus,broadband,multi-beam scanning and other features,Luneburg lens antennas are applied in multi-beam antenna,which overcomes the problem of gain loss produced by multi-beam parabolic antenna.Based on 3-D printing technique,Luneburg lens antennas by drilling holes are studied.Permittivity and loss tangent of the equivalent lens materials can be influenced by original materials,hole shapes,hole directions,and porosity.After tests,polystyrene with waxes may be the most appropriate materials for Luneburg lens with high strength.Permittivity with the shape of triangle is the lowest due to the homogeneity.Relative permittivities with the direction at a range of 15°-45°are lower while loss tangent at a range of 0°-30°.Radial directional holes are more appropriate for Luneburg lens.The relative permittivity is decreased with the increment of porosity.After calculations,the forecasts calculated by Looyenga and A-BG theory are more precise.Finally,Luneburg lens with two layers is fabricated by 3-D printing. 展开更多
关键词 Luneburg lens by DRILLING HOLES 3-D PRINTING technique PERMITTIVITY
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FABRICATION OF HIGHLY HYDROPHOBIC FILMS OF POLY(3-HEXADECYL PYRROLE) NANOPARTICLES BY LANGMUIR-BLODGETT TECHNIQUE
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作者 石高全 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第5期457-462,共6页
Thin films of poly(3-hexadecyl pyrrole) (P3HDP) nanoparticles have been fabricated by using Langmuir-Blodgett film deposition technique. The structures and morphology of the films were studied by using infrared sp... Thin films of poly(3-hexadecyl pyrrole) (P3HDP) nanoparticles have been fabricated by using Langmuir-Blodgett film deposition technique. The structures and morphology of the films were studied by using infrared spectroscopy, scanning and transmission microscopes. The experimental results demonstrated that the nanoparticles were formed by self-assembling P3HDP at air-water surface. The water contact angles of these films with different deposition layers were measured to be as high as 110°. 展开更多
关键词 Poly(3-hexadecyl pyrrole) LB technique High hydrophobicity.
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A Study of the Comets with Large Perihelion Distances C/2019 L3(ATLAS)and C/2019 O3(Palomar)
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作者 Alberto S.Betzler 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第9期199-213,共15页
This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS... This work analyzes the photometric data of the Oort spike comets C/2019 L3(ATLAS)and C/2019 O3(Palomar)obtained between 2016 and 2023 by the ATLAS network and the Belgian Olmen Observatory.The comets Palomar and ATLAS have a typical and unusually high activity level,respectively,based on the Afρparameter corrected to phase angle zero at perihelion.The absolute magnitude of comets ATLAS and Palomar in the o-band is 4.71±0.05 and 4.16±0.02 respectively.The cometary activity of comets ATLAS and Palomar probably began at r>13 au before perihelion and will end at r>14 au after perihelion,which means that they could remain active until the second half of 2026.The nucleus of comet ATLAS has a minimum radius of 7.9 km,and the nucleus of comet Palomar could be a little larger.The c-o colors of the comets ATLAS and Palomar are redder and bluer,respectively,at perihelion than the solar twin YBP 1194.These comets showed a bluish trend in the coma color with decreasing heliocentric distance.Comet Palomar probably had two outbursts after its perihelion,each releasing about 10^(8)kg of dust.The slopes of the photometric profile of the comae of these comets were between 1and 1.5,indicating a steady state during the observation campaign. 展开更多
关键词 individual C/2019 L3(ATLAS) C/2019 O3(Palomar) techniques:photometric methods:data analysis
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优质水稻新品种塔稻3号的选育与应用
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作者 韦继超 石元强 +6 位作者 余智斌 田西京 徐安阳 周相 俞洁 杜东 蔡军 《北方水稻》 CAS 2024年第2期44-46,共3页
塔稻3号是新疆塔里木河种业股份有限公司育成的优质水稻新品种,于2022年通过新疆维吾尔自治区农作物品种审定委员会审定。该品种分蘖能力强,抽穗成熟整齐一致,抗病性好,抗倒性强,丰产性表现较好,综合农艺性状优良。介绍了塔稻3号的选育... 塔稻3号是新疆塔里木河种业股份有限公司育成的优质水稻新品种,于2022年通过新疆维吾尔自治区农作物品种审定委员会审定。该品种分蘖能力强,抽穗成熟整齐一致,抗病性好,抗倒性强,丰产性表现较好,综合农艺性状优良。介绍了塔稻3号的选育过程、特征特性、产量表现,从播种、施肥、灌水、病虫草害防治等方面总结了其栽培技术要点。 展开更多
关键词 水稻 塔稻3 选育 栽培技术
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Variety Characteristics and Cultivation Techniques of Rape Changzayou 3
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作者 胡金荣 朱传霞 +3 位作者 薛高尚 杨鸿 罗晓玲 柏秀芳 《Agricultural Science & Technology》 CAS 2016年第9期2046-2047,共2页
High-quality hybrid rape Changzayou 3 is a new yellow-seed double-low rape variety with high yield, good resistance to diseases and lodging and high oil content, suitable for winter cropping in central China. Its high... High-quality hybrid rape Changzayou 3 is a new yellow-seed double-low rape variety with high yield, good resistance to diseases and lodging and high oil content, suitable for winter cropping in central China. Its high-yield cultivation tech- niques are mainly early seeding at proper time, thinning timely, rational close planting, scientific fertilization, control of diseases and pest and weeding. 展开更多
关键词 RAPE Variety characteristics Cultivation technique Changzayou 3
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两种3D打印导板在下颌角成形术中的适应证及应用效果研究
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作者 陈友利 安鹏 +7 位作者 周绍良 唐正龙 高琼 宋具昆 杨芷姗 王冬香 付玉娟 王宇 《华中科技大学学报(医学版)》 CAS CSCD 北大核心 2024年第4期494-500,共7页
目的分析不同数字化设计及3D打印导板在下颌角成形术中的应用效果。方法选取贵州医科大学附属口腔医院2022年1月至2023年1月收治的12例下颌角肥大患者作为研究对象。所有患者术前均行颅面部CT扫描用于三维模型重建,参考面部协调性及美... 目的分析不同数字化设计及3D打印导板在下颌角成形术中的应用效果。方法选取贵州医科大学附属口腔医院2022年1月至2023年1月收治的12例下颌角肥大患者作为研究对象。所有患者术前均行颅面部CT扫描用于三维模型重建,参考面部协调性及美观需求设计个性化下颌角截骨范围。所有患者均以下颌骨保留部分设计升支固定式截骨导板,以下颌角截除部分设计下颌下缘固定式截骨导板,术中根据不同3D打印导板使用情况分为升支固定组(组1)及下颌下缘固定组(组2)。比较两组患者术前术后下颌角形态变化。术后2周行颅面部CT扫描,重叠配准患者虚拟手术设计与手术后颅面部CT数据,测量手术设计与术后下颌角的偏差。结果所有患者均顺利完成下颌角截骨成形手术,患者对术后面型满意。组1患者术前下颌角均为外展型,组2患者中1例下颌角为外展型,其余患者下颌角为内卷型。所有患者术后下颌角角度显著高于术前(P<0.01),术后左、右侧下颌角角度对比差异无统计学意义(均P>0.05)。两组患者手术设计与术后下颌下缘之间前部、中部、后部偏差水平对比差异无统计学意义(均P>0.05)。结论数字化设计及3D打印导板引导下颌角截骨成形术具有较高的精确性,可获得良好的美容效果;升支固定式截骨导板适用于下颌角外展型患者,下颌下缘固定式截骨导板更适合下颌角内卷型患者。 展开更多
关键词 下颌角成形术 数字化设计 手术导板 3D打印技术
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Study on the 3D Seismic Data Field Hybrid Rendering Technique of Natural Gas Hydrate and Its Application
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作者 Pan LI Zhaojun ZHOU Meng HUANG 《International Journal of Technology Management》 2013年第2期50-52,共3页
3D visualization technology is a tool used for displaying, describing, and understanding the characteristics of geologic bodies, and features high efficiency, objective accuracy, visual expression, etc. In this paper,... 3D visualization technology is a tool used for displaying, describing, and understanding the characteristics of geologic bodies, and features high efficiency, objective accuracy, visual expression, etc. In this paper, the man-machine interactive interpretation and 3D visualization technology rapidly displaying and analyzing the 3D seismic data of hydrate ore volume is researched and developed using the hybrid rendering technique. Through the integrated interpretation on the 3D space structure, stratum, and seismic attributes, the visualized multi-attribute superimposition analysis is implemented for describing the spatial distribution characteristics of hydrate ore volume and exquisitely describing the subtle geological characteristics of hydrate ore volume. By the hybrid rendering technique, authentication and interpretation are provided for the geological exploration work, so as to greatly enhance the visualization and accuracy of the geological analysis, and also provide a good decision-making foundation for the subsequent development of resources. 展开更多
关键词 Natural Gas Hydrate 3D Seismic Data Hybrid Rendering technique
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THE STUDY OF THE NON-STEADY KINETICS OF THE OXYDEHYDROGENATION OF ETHANE TO ETHYLENE OVER THE CATALYST OF Mo-V-Nb/Al_2O_3 BY THE TECHNIQUE OF TEMPERATURE PROGRAMMED TRANSIENT RESPONSE AND ELECTRIC CONDUCTIVITY
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作者 Ren You ZHANG, Hong JIANG, Xiao Dong SUN Xiu Yin LIU, Fu Rong WANG, Shou Li BAI, Zong Qi XU (Department of Applied Chemistry, Beijing Institute of Chemical Technology) 100029 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第11期893-896,共4页
In this paper, instead of with the more expensive Fourier Transform Infrared Spectrometer(FTIR) a new technique of Temperature Programmed Transient Response(TP-TR) has been used with gas chromatography. Therefore, the... In this paper, instead of with the more expensive Fourier Transform Infrared Spectrometer(FTIR) a new technique of Temperature Programmed Transient Response(TP-TR) has been used with gas chromatography. Therefore, the TP-TR will be applied more widespreadly than ever before. With the technique of TP-TR and electric conductivity, the study is on the reaction mechanism and the adsorption behavior of the reactants and products to the present catalyst Mo-V-Nb/Al_2O_3 in the reaction from ethane through oxydehydrogenation to ethylene as the product. By Range-Kutta-Gill and Margarat methods, the kinetic parameters of the reaction elementary steps (i.e. rate constants, active energies and frequency factors) have been evaluated. The mathematical treatment coincides with the experimental results. 展开更多
关键词 TR THE STUDY OF THE NON-STEADY KINETICS OF THE OXYDEHYDROGENATION OF ETHANE TO ETHYLENE OVER THE CATALYST OF Mo-V-Nb/Al2O3 BY THE technique OF TEMPERATURE PROGRAMMED TRANSIENT RESPONSE AND ELECTRIC CONDUCTIVITY MO Al
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