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Covering corneal stromal lenticule for macular hole in pathological myopia

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1675-1680页

作者： Zi-Yan Tang Gang Qiao Xiao-Juan Zhang Li-Jun Xie Qiang-Xing Zou Chun-Mei He Long Zhao Hua-Qing Yang Yu Quan kui cao Hui Jiang Yu-Kun He Wanjiang Eye Hospital of Mianyang Mianyang 621000Sichuan ProvinceChina

AIM:To evaluate the clinical effect of a new surgery technique(covering corneal stromal lenticule,CSL)for macular hole(MH)in pathological ***:This was a prospective non-randomized series case *** eyes of 14 patients whose axial length were more than 29 mm and suffered from MH and macular hole retinal detachment(MHRD)were included in this *** cases were treated with 25-gauge pars plana vitrectomy(PPV)with internal limiting membrane(ILM)peeling,covering CSL and C_(3)F_(8) gas *** cases were followed for 6mo,and the best-corrected visual acuity(BCVA),healing status of MH,the reattached rate of retinal detachment(RD),and reoperation rate were ***:All cases were successfully performed the surgery and the postoperative follow-up was *** surgery,MHs were healed in all 14 eyes(100%,14/14)after assessed by optical coherence *** reattachment of retina was achieved in all 6 eyes(100%,6/6)with *** was improved in 12 eyes(85.71%,12/14),and had no significant change in 2 eyes(14.29%,2/14).The overall mean BCVA was improved from 1.80±0.77 to 0.82±0.46 logMAR(F=10.46,P<0.01).No serious complications occurred in all ***:The new surgery technique(covering CSL)has high reattached rate of RD and high healing rate of MH in pathological myopia in the preliminary *** it can effectively improve the visual function of *** new technique offers meaningful new ideas for treating refractory MH in pathological myopia.

关键词： corneal stromal lenticule macular hole pathological myopia

实-药芯多丝电弧复合焊中药芯焊丝位置对焊接稳定性的影响

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材料热处理学报 2024年第6期45卷 193-201页

作者：向婷方振龙马强曹增奎张健天津职业技术师范大学机械工程学院天津300222 天津市金桥焊材集团股份有限公司天津300300

为了实现高强钢的优质高效焊接,提出了一种全新的Q960E高强钢的高效焊接工艺,即实-药芯多丝电弧复合焊工艺,该工艺通过一把集成式三丝焊枪实现两根实心焊丝复合一根药芯焊丝,既可以利用药芯焊丝实现焊接接头力学性能的优化,又可以利用3... 详细信息

为了实现高强钢的优质高效焊接,提出了一种全新的Q960E高强钢的高效焊接工艺,即实-药芯多丝电弧复合焊工艺,该工艺通过一把集成式三丝焊枪实现两根实心焊丝复合一根药芯焊丝,既可以利用药芯焊丝实现焊接接头力学性能的优化,又可以利用3根焊丝实现高效焊接。其中药芯焊丝可以从两实心焊丝的正前方、正后方及侧面送入,通过对比分析焊接过程、焊道成形得出最佳药芯焊丝作用位置,并对最佳药芯焊丝作用位置下焊接接头的组织和显微硬度展开分析。结果表明:当药芯焊丝从正后方或侧面送入时,其中一根实心焊丝易与熔池接触发生短路过渡,前者会导致焊道宽窄不一,后者会导致焊道明显偏向药芯焊丝送入一侧。当药芯焊丝从正前方送入时,药芯焊丝呈一脉多滴过渡,且两实心焊丝均为一脉一滴过渡,此时焊接过程稳定,焊后焊道成形较好,焊道横截面形貌呈“双峰”状,是最佳的药芯焊丝送入位置。此外,当药芯焊丝从正前方送入时,焊缝区组织主要为细小的针状铁素体,粗晶区组织主要为粗大的板条马氏体和少量粒状贝氏体,细晶区组织主要为细小的马氏体,不完全淬火区组织主要为回火马氏体。此外,热影响区同时出现了软化和硬化现象,近不完全淬火区的母材硬度最低,仅为296 HV,完全淬火区硬度最高,达到396 HV,母材和焊缝区的硬度在320~340 HV之间。

关键词： Q960E高强钢实-药芯多丝电弧复合焊药芯焊丝作用位置焊接稳定性焊道成形

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黑河源区不同植被类型土壤粒径分形特征研究

草地学报 2024年第5期32卷 1459-1470页

作者：刁二龙曹广超刘英赵青林曹生奎袁杰汉光昭张富玲青海师范大学地理科学学院青海省自然地理与环境过程重点实验室青海西宁810008 青海师范大学青藏高原地表过程与生态保育教育部重点实验室青海西宁810008 青海省人民政府-北京师范大学高原科学与可持续发展研究院青海西宁810008 青海农牧业工程咨询有限公司青海西宁810008 青海省自然资源遥感中心青海西宁810008

本研究以黑河源区为研究区,运用分形理论研究了该区域3种主要植被类型土壤粒径分形特征,并分析了土壤粒径分形与环境因子的关系。结果表明:草地砂粒含量最大(38.83%),灌木林地次之(26.11%),乔木林地砂粒含量最低(22.76%),土壤单重分形维... 详细信息

本研究以黑河源区为研究区,运用分形理论研究了该区域3种主要植被类型土壤粒径分形特征,并分析了土壤粒径分形与环境因子的关系。结果表明:草地砂粒含量最大(38.83%),灌木林地次之(26.11%),乔木林地砂粒含量最低(22.76%),土壤单重分形维数(Single fractal dimension,D)大小表现为草地(2.60)<灌木林地(2.64)<乔木林地(2.65);乔木林地、灌木林地和草地的土壤粒径均呈非均匀性分布,与乔木林地和灌木林地相比,草地的土壤粒径分布非均匀性最高;D与土壤粘粒、粉粒含量呈极显著正相关关系,与砂粒含量呈极显著负相关关系,而容量维(D 0),信息维(D 1),关联维(D 2)与土壤各粒级含量的关系与D相反。此外,地形、植被盖度和土壤理化因子对3种植被类型土壤分形维数产生不同程度的影响。综上,不同植被类型土壤粒径分形特征差异明显,分形维数主要受土壤粒径影响,其它因子通过影响土壤颗粒组成从而对分形维数产生影响。研究结果可为黑河源区土地资源的科学管理和合理利用提供参考。

关键词：黑河源区土壤粒径分形维数植被类型

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SYNTHESIS OF CROSS-CONJUGATED(p-PHENYLENE)S-POLY(p-PHENYLENEVINYLENE)S HYBRIDS WITH LOW CONTENT OF STRUCTURAL DEFECTS

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Chinese Journal of Polymer Science 2007年第2期25卷 171-179页

作者： Shi-jun Zheng Qun Xu Shao-kui cao College of the Material Science and Engineertng Zhengzhou University Zhengzhou 450052 China

The novel shish-kebab-type liquid crystalline cross-conjugated （p-phenylene）s-poly（p-phenylenevinylene）s hybrid was synthesized through Gilch polymerization. Their structures and properties were characterized by NMR, GPC, DSC, X-ray diffraction and polarizing optical microscope （POM）. ^1H-NMR investigation of the polymers indicates that the shish-kebab-structure has a strong ability to suppress the structural defects in the polymers. The polymers are enantiotropic liquid crystals. The melting point （Tm） of the polymers decreases when the length of the alkoxy tails of the mesogenic units increases. The mesophase was identified by X-ray diffraction method. They showed not only a smectic LC phase, but also a strong green fluorescence in chloroform. The maximum absorption band of the ＂kebabs＂ of the two, 5-bis（4＇- alkoxyphenyl）benzene at 280 nm did not appear in absorption spectra of the polymers. The same phenomena were also observed in the fluorescence spectra. These results imply that the polymers have formed a cross-conjugated uniform structure and achieved an extended n-conjugation polymer.

关键词： Gilch polymerization Conjugated polymer Liquid crystal Shish-kebab Fluorescence.

Comparative study of bacterial status from conjunctival sac of the elder Qiang minority and Han people with dry eye in Sichuan,China

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International Journal of Ophthalmology(English edition) 2012年第3期5卷 343-347页

作者： Yue Zhang, kui cao Department of Ophthalmology Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu 610072 Sichuan Province China Mianyang Wanjiang Ophthalmologic Hospital Mianyang 621000 Sichuan Province China Department of Clinical Laboratory Sichuan Academy of Medical Sciences and Sichuan Provincial People's Hospital Chengdu 610072 Sichuan Province China Hospital of Traditional Chinese Medclicine Affiliated to Luzhou Medical College Luzhou 646000 Sichuan ProvinceChina The Fourth People's Hospital of Zigong City. Zigong 643000 Sichuan Province China

AIM: To compare the status of bacteria in the conjunctival sac from the elder Qiang minority and Han people with dry eyes in Sichuan, China. METHODS: Total of 54 elder Qiang people with dry eyes (108 eyes) were examined by cluster sampling. In the similar habitation region of Han people, 80 (160 dry eyes) Han people were analyzed as the control group. The bacteria was separated from the inferior palpebral conjunctiva, then inoculated on blood plate for 48 hours and identified. RESULTS: Totally 24 strains of bacteria were cultured in either Qiang minority or Han c populations with 3 strains of them existed in both ethnic groups. The commonest bacteria in conjunctival sac in two ethnic groups were non-pathogenic bacterium. The composition of Corynebacterium in Han people (54.1%) was significantly higher than that in Qiang minority (27.4%) (chi(2)=11.6721, P=0.0006). The percentage of Sphingomonas Paucimobilis in Qiang people was higher than that in Han people (chi(2)=18.6442, P=0.0000). However, there was no significant difference between Qiang minority and Han people either in bacterial positive rate in conjunctival sac, or the composition of bacteria species and strains, or the composition of staphylococcus epidemids between two ethnic populations. CONCLUSION:There was no significant difference of bacterial positive rate in conjunctival sac from the elder of Qiang minority and Han people with dry eye, but the species of bacteria were different.

关键词： conjunctival sac bacteria dry eye

Integrating Color and Spatial Feature for Content-Based Image Retrieval

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Wuhan University Journal of Natural Sciences 2002年第3期7卷 290-296页

作者： cao kui Feng Yu-cai Sch. of Comp. Sci. and Technol. Huazhong Univ. of Sci. and Technol. Wuhan 430074 China

In this paper, we present a novel and efficient scheme for extracting, indexing and retrieving color images. Our motivation was to reduce the space overhead of partition-based approaches taking advantage of the fact that only a relatively low number of distinct values of a particular visual feature is present in most images. To extract color feature and build indices into our image database we take into consideration factors such as human color perception and perceptual range, and the image is partitioned into a set of regions by using a simple classifying scheme. The compact color feature vector and the spatial color histogram, which are extracted from the seqmented image region, are used for representing the color and spatial information in the image. We have also developed the region-based distance measures to compare the similarity of two images. Extensive tests on a large image collection were conducted to demonstrate the effectiveness of the proposed approach.

关键词： color distribution spatial color histogram region-based image representation and retrieval similarity matching integrating of single features

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情势变更制度在建设工程合同中的推定和思考

吉林水利 2024年第4期 66-68,78页

作者：曹逵张紫湜王冠中国港湾工程有限责任公司北京100027 中国南水北调集团东线有限公司北京100070

情势变更制度作为契约严守原则的补充,若理解和使用不当在很大程度上会引发建设工程施工合同双方的巨大争议。考虑到建设工程施工合同具有多样性,相关方在合同拟定和执行的过程中经常对不可抗力事件、不可预见等因素存在认知偏差,且缺... 详细信息

情势变更制度作为契约严守原则的补充,若理解和使用不当在很大程度上会引发建设工程施工合同双方的巨大争议。考虑到建设工程施工合同具有多样性,相关方在合同拟定和执行的过程中经常对不可抗力事件、不可预见等因素存在认知偏差,且缺乏合同索赔条款等情况,导致建设工程施工合同中的受损失方更加主动地寻求情势变更制度下的补偿和救济措施。因此,基于国内对于情势变更制度的发展和相关法规,对易淆点进行分类讨论,进一步分析情势变更制度在我国法律中的适用性和可行性,在合理保护受损失方权益和公平原则下,实现合同存续的目的。

关键词：建设工程合同管理情势变更不可抗力商业风险

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交错图腾柱PFC改进平均电流控制策略研究

电力电子技术 2024年第8期58卷 40-44页

作者：刘欢曹洪奎刘玉爽辽宁工业大学电子与信息工程学院辽宁锦州121001

针对工作在连续导通模式下,图腾柱无桥(TTPL)功率因数校正(PFC)电路输入电流总谐波畸变率(THD)较大和系统动态响应不足的问题,此处研究了一种两相交错并联图腾柱PFC拓扑结构。根据该拓扑结构,分析了传统比例积分(PI)控制器在电流跟踪控... 详细信息

针对工作在连续导通模式下,图腾柱无桥(TTPL)功率因数校正(PFC)电路输入电流总谐波畸变率(THD)较大和系统动态响应不足的问题,此处研究了一种两相交错并联图腾柱PFC拓扑结构。根据该拓扑结构,分析了传统比例积分(PI)控制器在电流跟踪控制的局限性,提出了一种优化输入电流THD的PFC复合控制策略。该数字复合控制策略电流内环采用比例谐振(PR)控制器,改善了系统环路的动态响应性能,通过引入自适应陷波滤波器滤除电压外环二次谐波,提高了系统的抗扰动性能。同时采用了基于双极控制的过零点尖峰电流抑制策略,有效改善变换器的输入电流畸变。最后通过二阶广义积分(SOGI)锁相环对变换器电流内环超前效应进行补偿,进一步抑制输入电感电流尖峰。Matlab仿真结果表明,该控制策略可有效地减小网侧电流畸变,相比平均电流控制网侧输入电流THD下降了1.79%,并提升了输出侧的动态响应指标。

关键词：变换器图腾柱功率因数校正二阶广义积分

Nitrogen Leaching in Vegetable Fields in the Suburbs of Shanghai

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Pedosphere 2005年第5期15卷 641-645页

作者： cao Lin-kui CHEN Guo-Jun LU Yi-Tong School of Agriculture and Biology Shanghai Jiaotong University Shanghai 201101 （China）

Nitrogen (N) leaching in vegetable fields from December 2002 to May 2003 with equal dressings of total N for asequential rotation of Chinese flat cabbage (Brassica chinensis L. var. rosularis) and lettuce (Lactuca sativa L.) in asuburban major vegetable production base of Shanghai were examined using the lysimeter method to provide a scientificbasis for rational utilization of nitrogen fertilizers so as to prevent nitrogen pollution of water resources. Results showedthat leached N consisted mainly of nitrate N, which accounted for up to more than 90% of the total N loss and couldcontribute to groundwater pollution. Data also showed that by partly substituting chemical N (30%) in a basal dressingwith equivalent N of refined organic fertilizer in the Chinese flat cabbage field, 64.5% of the leached nitrate N was reduced,while in the lettuce (Lactuca sativa L.) field, substituting 1/2 of the chemical N in a basal dressing and 1/3 of the chemicalN in a top dressing with equivalent N of refined organic fertilizers reduced 46.6% of the leached nitrate N. In the two-year sequential rotation system of Chinese flat cabbage and lettuce, nitrate-N leaching in the treatment with the highestamount of chemical fertilizer was up to 46.55 kg ha-1, while treatment plots with the highest amount of organic fertilizerhad only 17.58 kg ha-1. Thus, partly substituting refined organic fertilizer for chemical nitrogen in the first two seasonshas a great advantage of reducing nitrate-N leaching.

关键词： leaching loss nitrogen organic fertilizer vegetable field