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Correlation Combination Ambiguity Removing Technology for Acquisition of Sine-Phased BOC(kn,n) Signals

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China Communications 2015年第4期12卷 86-96页

作者： liu Wen xi Yue DENG Zhongliang jiao Jichao YIN Lu Laboratory of Intelligent Communication Navigation and Micro/Nano-SystemsBeijing University of Posts and Telecommunications

Binary Offset Carrier(BOC) has been chosen as one of modulation methods in the future Global Navigation Satellite Systems(GNSS). Even though BOC signals can bring several advantages such as better track performance and higher positioning accuracy, there is a drawback that the autocorrelation functions have multiple side-peaks if BOC modulation is adopted. This characteristic will lead to false acquisition and the tracking loop will be locked in false phase point. The proposed Correlation Combination Ambiguity Removing Technology(CCART) cancelled all the side-peaks of the sine-phased BOC(kn,n) signals completely by making use of two kinds of correlation functions. Two kinds of sub-correlation functions were combined separately and then final correlation function without side-peaks was acquired. The simulation results are given and compared with other techniques. It is shown that acquisition will not be degraded with the increase of k.

关键词： GNSS unambiguous acquisition,sine-phased BOC(kn,n) combination ofcorrelation functions

基于尺寸效应的钛合金二维超声辅助精密切削特性研究

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河南理工大学学报（自然科学版） 2025年第1期44卷 117-123页

作者：王鑫刘建慧焦锋新乡航空工业(集团)有限公司河南新乡453000 河南理工大学机械与动力工程学院河南焦作454000

目的为了减少尺寸效应对精密加工的影响,提高钛合金微尺度切削的加工精度与表面质量,方法将特种加工理论和精密切削方法相结合,提出二维超声辅助精密切削方法。首先,基于ABAQUS力-热耦合模型分析二维超声辅助精密切削钛合金的切削过程,... 详细信息

目的为了减少尺寸效应对精密加工的影响,提高钛合金微尺度切削的加工精度与表面质量,方法将特种加工理论和精密切削方法相结合,提出二维超声辅助精密切削方法。首先,基于ABAQUS力-热耦合模型分析二维超声辅助精密切削钛合金的切削过程,探究精密切削与二维超声辅助精密切削的切削力学特性;其次,通过试验以超声振幅、切削深度与刃口半径的比值(a_(p)/r_(n))为因素,分析尺寸效应作用下超声振动切削中切削力及单位切削力的变化规律;最后,对比分析精密切削与二维超声辅助精密切削在不同切削深度与刃口半径的比值(a_(p)/r_(n))下的表面形貌特征。结果结果表明,随着切削深度与刃口半径的比值(a_(p)/r_(n))增大,精密切削钛合金表面形貌出现黏结、凹坑、耕犁现象,而二维超声辅助精密切削加工表面则出现均匀、完整的网状表面纹理特征。另外,二维超声辅助精密切削加工单位切削力远小于精密切削加工的,且随着振幅增大,单位切削力的增长比值由57.7%降至45.2%。结论二维超声辅助精密切削能够显著改善尺寸效应中产生的负前角效应和犁切现象,降低单位切削力,提高切削过程的稳定性,在提高钛合金微尺度切屑加工精度和表面质量方面具有重要应用价值。

关键词：二维超声辅助切削尺寸效应刃口半径切削力

Synthesis of energetic materials by microfluidics

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Defence Technology(防务技术) 2025年第2期44卷 306-319页

作者： Shuo liu Chuanyu Zhang Yanlan Wang Xueyong Wei School of Mechanical Engineering Xi'an Jiaotong UniversityXi'an 710049China School of Instrument Science and Technology Xi'an Jiaotong UniversityXi'an 710049China Science and Technology on Applied Physical Chemistry Laboratory Xi'an 710061China

Energetic materials,characterized by their capacity to store and release substantial energy,hold pivotal significance in some fields,particularly in defense ***,with its ability to manipulate fluids and facilitate droplet formation at the microscale,enables precise control of chemical *** scholarly endeavors have increasingly harnessed microfluidic reactors in the realm of energetic materials,yielding morphologically controllable particles with enhanced uniformity and explosive ***,crucial insights into microfluidic-based methodologies are dispersed across various publications,necessitating a systematic ***,this review addresses this gap by concentrating on the synthesis of energetic materials through ***,the methods based on micro-mixing and droplets in the previous papers are summarized and the strategies to control the critical parameters within chemical reactions are discussed in ***,the comparison in terms of advantages and disadvantages is *** demonstrated in the last section regarding perspectives,challenges such as clogging,dead zones,and suboptimal production yields are non-ignoble in the promising fields and they might be addressed by integrating sound,optics,or electrical energy to meet heightened *** comprehensive overview aims to consolidate and analyze the diverse array of microfluidic approaches in energetic material synthesis,offering valuable insights for future research directions.

关键词： Microfluidic technology Energetic materials synthesis Micro-mixing Micro-droplets

Lattice-mismatch-induced formation of defect-rich Pd-Cu alloy nanocages for enhanced formic acid oxidation activity

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Science China Chemistry 2025年第2期68卷 481-491页

作者： Zhaojun liu Zhengyan Wang Zhaoyu Wang Hao Yuan Yuke Bai xiaoxiao Wang Zerui Mu Chunxia Wu Kai liu Zhun Hu Chuanbo Gao Sate Key Laboratory of Multiphase Flow in Power Engineering Frontier Institute of Science and TechnologyXi’an Jiaotong UniversityXi’an 710049China Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Crystallographic defects in noble metal nanocrystals are recognized as highly active catalytic sites,significantly enhancing activities in many important *** their importance,synthesizing noble metal nanocrystals with a high density of defects poses a considerable synthetic ***,we present a novel lattice mismatch-induced formation mechanism to create high-density defects in noble metal *** approach takes advantage of lattice mismatch to enable nonepitaxial nucleation and growth of a noble metal on a foreign metal substrate,forming abundant noble metal crystallites with random lattice orientations not dictated by the substrate *** these crystallites grow extensively,they merge,forming numerous grain boundaries and yielding defect-rich noble metal ***-rich alloy nanocrystals can also be synthesized through a subsequent vacancy-diffusion alloying *** take defective PdCu alloy nanocages as an example and demonstrate the effectiveness of crystallographic defects in enhancing catalytic performance of noble metal *** nanocages exhibit superior activity in the electrocatalytic formic acid oxidation reaction,which is 1.6 times greater than their defect-free *** strategy offers a new avenue for creating defect-rich noble metal nanocrystals as highly efficient catalysts for a wide array of catalytic applications.

关键词： noble metal nanocrystals defects non-epitaxial growth electrocatalysis formic acid oxidation reaction

联合多源遥感数据的黄土高原(甘肃区)森林覆盖变化及驱动力分析

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科学技术与工程 2025年第1期25卷 54-66页

作者：刘博牛全福王刚刘明志王浩雷姣姣兰州理工大学土木工程学院兰州730050 甘肃省应急测绘工程研究中心兰州730050 甘肃大禹九洲空间信息科技有限公司院士专家工作站兰州730000

黄土高原作为中国西部地区的自然生态屏障,为国家可持续发展做出了积极贡献。黄土高原(甘肃区)生态环境的治理与修复对中国生态文明建设战略的实施具有关键作用,为监测2008—2018年黄土高原(甘肃区)森林资源变化情况,基于云平台,联合Lan... 详细信息

黄土高原作为中国西部地区的自然生态屏障,为国家可持续发展做出了积极贡献。黄土高原(甘肃区)生态环境的治理与修复对中国生态文明建设战略的实施具有关键作用,为监测2008—2018年黄土高原(甘肃区)森林资源变化情况,基于云平台,联合Landsat、PALSAR及地形数据,探究光谱指数、后向散射、纹理及地形特征在森林资源信息获取方面的优势,运用随机森林特征优选算法获取研究区10年间森林覆盖时空分布并基于地理探测器进行因子探测。结果表明:随机森林特征优选算法可以有效筛选特征重要信息,总体精度可达91.88%,Kappa系数为0.91。联合Landsat、PALSAR及地形数据的实验方案精度明显高于使用单一数据源的森林分类结果,四期分类结果总体精度分别为86.65%、88.23%、90.15%、89.86%。10年间研究区森林面积净增加0.60×10^(4) km^(2);森林增加的区域主要分布于庆阳市中东部、平凉市东部、天水市中部和临夏回族自治州西部地区,而森林退化主要出现在定西市西南部和临夏回族自治州中东部地区。单因子探测中土地利用类型是森林覆盖变化的主导因子,适宜性的土壤类型的空间分布和降雨量的辅助作用,为植树造林成活率和森林健康生长提供了良好的自然条件。

关键词：黄土高原(甘肃区) 特征优选遥感监测地理探测器

人类学、辩证法与历史唯物主义——劳伦斯·克拉德对马克思人类学思想的解读与建构

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求是学刊 2025年第1期52卷 29-39页

作者：陈希刘勇李文爽武汉科技大学马克思主义学院武汉430081 湖北省意识形态建设研究院浙江大学马克思主义学院杭州310013

劳伦斯·克拉德编辑出版了晚年马克思的“人类学笔记”,为深入理解马克思及其思想提供了新视角。克拉德通过比较马克思恩格斯在自然观与历史观上的思想差异,剖析了两人对辩证法的不同理解与运用。同时,克拉德指出马克思的人类学思想经... 详细信息

劳伦斯·克拉德编辑出版了晚年马克思的“人类学笔记”,为深入理解马克思及其思想提供了新视角。克拉德通过比较马克思恩格斯在自然观与历史观上的思想差异,剖析了两人对辩证法的不同理解与运用。同时,克拉德指出马克思的人类学思想经历了从哲学人类学到经验人类学的转向,密切了马克思与人类学之间的联系。面对传统人类学亲理论而远实践、重抽象而薄辩证的状态,克拉德强调了马克思关于人的论述的统一性,并试图以此为基点,以人对自然的关系与社会内部关系为两翼,建构一门完整的人的科学,即马克思主义人类学。

关键词：劳伦斯·克拉德马克思人类学

99Tcm-MIBI显像阴性的原发性甲状旁腺功能亢进症合并甲状腺乳头状癌的治疗选择

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中华内分泌代谢杂志 2025年第1期41卷 61-64页

作者：于静雯张曦刘海蔚海南省人民医院内分泌科海口海南省人民医院心血管内科海口

原发性甲状旁腺功能亢进症(PHPT)是临床上相对常见的一种内分泌疾病。对于该疾病的诊断、定性易, 但常出现锝-99m-甲氧基异丁基异腈(99Tcm-MIBI)显像阴性而导致定位困难的情况, 常导致临床治疗的困局, 即是否选择手术治疗。本文列举的2... 详细信息

原发性甲状旁腺功能亢进症(PHPT)是临床上相对常见的一种内分泌疾病。对于该疾病的诊断、定性易, 但常出现锝-99m-甲氧基异丁基异腈(99Tcm-MIBI)显像阴性而导致定位困难的情况, 常导致临床治疗的困局, 即是否选择手术治疗。本文列举的2例99Tcm-MIBI显像阴性的PHPT患者均同时合并甲状腺乳头状癌(PTC), 进行传统手术探查后, 手术医生成功定位并切除了甲状旁腺功能亢进症的病灶, 并对PTC进行了相应处理, 术后随访患者恢复良好。本文尝试对积极手术的原因加以分析, 以期提高对此类情形的临床认知。

关键词：原发性甲状旁腺功能亢进症 99Tcm-MIBI显像阴性甲状腺乳头状癌

Analysis of risk factors for bile leakage after laparoscopic exploration and primary suture of common bile duct

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World Journal of Gastrointestinal Surgery 2025年第3期17卷 278-287页

作者： Qing-Song Yang Meng Zhang Chang-Song Ma Da Teng Ao Li Ji-Dong Dong xi-Fei Wang Fu-Bao liu Department of Hepatopancreatobiliary Surgery Affiliated Chuzhou Hospital of Anhui Medical University(The First People’s Hospital of Chuzhou)Chuzhou 239001Anhui ProvinceChina Department of Hepatobiliary and Pancreatic Surgery General SurgeryThe First Affiliated Hospital of Anhui Medical UniversityHefei 230022Anhui ProvinceChina

BACKGROUND Bile leakage is a common complication following laparoscopic common bile duct exploration(LCBDE)with primary duct closure(PDC).Identifying and analyzing the risk factors associated with bile leakage is crucial for improving surgical *** To explore the value analysis of common risk factors for bile leakage after LCBDE and PDC,with a focus on strict adherence to *** Clinical data of 106 cases undergoing LCBDE+PDC in the Hepatobiliary and Pancreatic Surgery Department(Division 1)of Chuzhou First People’s Hospital from April 2019 to March 2024 were *** and multiple factor regression analysis were conducted on common risk factors for bile *** change in surgical time was analyzed using the cumulative summation(CUSUM)method,and the minimum number of cases required to complete the learning curve for PDC was obtained based on the proposed fitting curve by identifying the CUSUM maximum *** Multifactor logistic regression analysis showed that fibrinous inflammation and direct bilirubin/indirect bilirubin were significant independent high-risk factors for postoperative bile leakage(P<0.05).The time to drain removal and length of hospital stay in cases without bile leakage were significantly shorter than in cases with bile leakage(P<0.05),with statistical *** CUSUM method indicated that a minimum of 51 cases were required for the surgeon to complete the learning curve(P=0.023).CONCLUSION With a good assessment of duodenal papilla sphincter function,unobstructed bile-pancreatic duct convergence,exact stone clearance,and sufficient surgical experience to complete the learning curve,PDC remains the preferred method for bile duct closure and is worthy of clinical promotion.

关键词： Laparoscopic common bile duct exploration Primary duct closure Bile leakage Risk factor analysis Cumulative summation

垃圾飞灰与粉煤灰协同熔融制备CAS体系微晶玻璃的研究

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材料导报 2025年第1期39卷 169-176页

作者：魏鑫焦芬刘维顾丝雨汪辰覃文庆中南大学资源加工与生物工程学院长沙410083

将水洗预处理后的生活垃圾焚烧飞灰(WFA)与粉煤灰(CFA)协同处置,通过“熔融-热压成形”一步法热处理制备CaO-Al_(2)O_(3)-SiO_(2)体系微晶玻璃。结果表明:添加15 g辅料、3 g晶核剂(TiO_(2))和6 g碳粉,当WFA、CFA和SiO_(2)用量分别为35 g... 详细信息

将水洗预处理后的生活垃圾焚烧飞灰(WFA)与粉煤灰(CFA)协同处置,通过“熔融-热压成形”一步法热处理制备CaO-Al_(2)O_(3)-SiO_(2)体系微晶玻璃。结果表明:添加15 g辅料、3 g晶核剂(TiO_(2))和6 g碳粉,当WFA、CFA和SiO_(2)用量分别为35 g、35 g和25.5 g,m(CaO)/m(SiO_(2))为0.54时,在1 050℃下热处理1 h,得到晶相分布均匀、相对结晶度为93.66%的微晶玻璃,其密度为2.79 g/cm^(3)、吸水率为0.04%、耐酸度为99.71%、耐碱度为99.83%、抗压强度为350.87 MPa、维氏硬度为6.52 GPa。经毒性浸出测定,该微晶玻璃符合国家标准,为垃圾飞灰的高值化利用提供了技术保障。

关键词：垃圾飞灰协同配比微晶玻璃物化性能重金属