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整流站采用二极管整流器能够提升远距离大容量海上风电直流送出系统的经济性和可靠性。提出了基于24脉动二极管整流器的海上风电并网系统中交流滤波器的优化配置方法。首先，明确了基于24脉动二极管整流器的海上风电送出系统结构，阐述了24脉动二极管整流器的基本原理。然后，计算了24脉动二极管整流器的无功功率需求，对于24脉动二极管整流器，可以将设计复杂的交流滤波器简化为电容器，通过对有功功率变化范围内不同容量电容器滤波效果进行扫描，提出了综合考虑滤波效果和滤波器容量的交流滤波器无功容量优化方法。最后，在PSCAD/EMTDC中对基于24脉动二极管整流器的海上风电送出测试系统进行了谐波分析和交流滤波器优化设计。

酸价（acid value, AV）指示油脂中游离脂肪酸(free fatty acid, FFA)含量，是油脂和含油食品最重要的质量指标和安全指标之一。针对现行AV测定标准的酸碱中和滴定技术的共性与非特异性的局限，旨在给复杂基质样品的特异性定量FFA或AV提供新思路，综述了最具代表性的FFA特异性检测技术——铜皂络合比色法的近70年的研究进展。阐述了有机相溶解液的毒性与显色强度之间的矛盾化解历程、铜盐-吡啶水相染色液的演化史、FFA的铜皂络合物结构解析过程，以及从pH调控的经典络合显色理论到以吡啶与铜离子摩尔比为核心的络合显色理论的新发展。吡啶与铜离子摩尔比为\[1，3）的络合显色理论、具有增强显色强度和抑制乳化作用的乙酸盐-乙酸缓冲体系的中性染色液、低毒性溶剂替代传统高毒性苯的有机相溶解液，这三大创新使经典铜皂络合比色法突破了长期存在的试剂毒性与显色稳定性等瓶颈，成为复杂基质样品的特异性定量FFA或AV的理想方法。 Acid value(AV) indicates the content of free fatty acids(FFA) in oils and fats, which is one of the most important quality and safety indicators of oils and fats and oily foodstuffs. In view of the commonness and non-specificity limitations of the current acid-base neutralization titration techniques for AV determination standards, a new idea for the specific quantification of FFA or AV in complex matrix samples is aimed to offer. The research progress of cupric acetate-pyridine complexation colorimetry, the most representative technology for the specific determination of FFA in the nearly 70 years, was reviewed. The conflict resolution process between the toxicity of organic phase solution and color intensity, the evolution history of cupric acetate-pyridine colorimetric aqueous phase dyeing solution, the structure analysis process of cupric acetate-pyridine complex of FFA, and the new development of complexation color theory from the classical theory with pH regulation to the new theory with pyridine/copper ion mole ratio as the core were described. Pyridine/copper ions mole ratio \[1, 3) of the complexation color theory, acetate - acetic acid buffer′s neutral dyeing liquid with enhancement of color strength and inhibition of the emulsification, low toxic solvent instead of traditional high toxicity of benzene dissolved organic phase, three big innovation make the classic colorimetric method break through the bottleneck of toxicity and color stability etc., which is expected to be an ideal method for the specific quantification of FFA or AV in complex matrix samples.

为了深入了解内置工字形CFRP型材的方钢管混凝土中长柱的力学性能,通过试验与有限元分析结合的方式研究了其在双向偏心状态下的工作机理及破坏形态。在此基础上,对典型构件进行了全过程分析,研究了偏心率、含钢率、长细比、钢材屈服强度以及混凝土抗压强度对构件受力性能的影响。研究结果表明,内置工字形CFRP型材的方钢管混凝土中长柱的荷载-挠度曲线可分为弹性阶段、弹塑性阶段、塑性强化阶段以及下降阶段4个阶段;CFRP型材与钢材及混凝土有着良好的协同工作性能,可加强对混凝土的约束作用,CFRP型材最终发生脆性破坏;构件的极限承载力随着长细比及偏心距的增加而降低,随着含钢率、钢材屈服强度及混凝土强度的增加而提高;构件的初始刚度随着长细比及偏心距的增加而降低。

对于高码率、长距离、色散管理准线性光纤传输,IFWM（信道内四波混频）是影响信号传输质量的主要非线性效应之一。文章采用分布傅里叶的计算方法,推导了描述准线性传输系统传输过程的数值计算模型,介绍了一种经济有效的、色散管理结合脉冲预展宽的非线性补偿方案。经过预展宽后,输出端鬼脉冲的强度仅为预展宽前的1/4。计算结果表明,该方案可有效抑制IFWM,获得理想的补偿效果,对今后高速光纤通信系统的设计具有一定的指导意义。

文章通过数值计算研究了掺铒光纤放大器（EDFA）中超短光脉冲放大的情况。结果表明,当相邻两超短脉冲的初始间距较小时,两脉冲在放大过程中会相互吸引,并产生新的子脉冲,从而导致放大效果变差。增大初始间距并不能有效地改善放大效果。为此,提出对输入光脉冲对引入合适的初始啁啾的方法,该方法可以减小因光脉冲互作用带来的负面影响,提高脉冲放大质量。

利用数值计算的方法证明,采用色散渐减光纤（DDF）构成的马赫-曾德干涉仪（MZI）不仅可以压缩高阶光孤子,而且能有效地消除压缩脉冲后的脉座。研究表明:通过灵活地调整MZI的双臂可以获得高质量脉冲;同时得出了使干涉仪具有良好压缩特性的耦合器的功分比范围,这对实验中参数的选取有一定的指导意义;研究还发现,DDF即使选用较大的首末色散比系数,仍然能得到高质量的脉冲。

光纤布拉格光栅（FBG）由于其独特的光学特性和灵活的设计特点,在光通信系统中有着广泛的应用,包括光脉冲压缩、全光开关、全光复用/解复用器、色散补偿器和光存储等等。文章主要对FBG在光脉冲压缩中的应用进行了分析,并对几种压缩器的结构、原理和性能作了介绍。

文章比较了3类色散渐减光纤环镜的光脉冲压缩特性,结果发现,不考虑高阶效应时,线性渐减光纤环镜需要的最佳光纤长度最短,压缩后的光脉冲质量较高;考虑高阶效应后,情况恰恰相反,高斯渐减光纤环镜需要的最佳光纤长度最短,压缩质量较高,但此时3种类型的光纤构成的非线性光纤环镜压缩特性差别不大。

【目的】了解性病高危人群中阴道分泌物的病原学情况及阴道念珠菌病的发病情况。【方法】用涂片和培养法对 1 301 例STDs门诊 病人和 224 例妇教人员的阴道分泌物进行了病原学检测及酵母菌的培养鉴定。【结果】1 525 例性病高危人群中,其阴道分泌物查到酵母菌 487 例,滴虫 242 例,加特纳菌235 例,多形核白细胞G -双球菌 32 例; 对分离培养的 238 株酵母菌进行鉴定,其中白色念珠菌 204 株,光滑念珠菌 17 株,近平滑念珠菌11 株,热带念珠菌2 株,埃莫毕赤、清酒、无名和土生念珠菌各1 株。【结论】性病高危人群中阴道分泌物的病原菌是复杂的,但 仍以酵母菌占首位,带菌率达31. 9%( 487 /1 525) ,其优势菌以白色念珠菌为主,占85. 7%( 204 /238); 淋菌的带菌率也高达 2. 1%( 32/1 525) ,应引 起重视。

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The Prostate Imaging Reporting and Data System (PI-RADS) of MRI has been applied in the international medical community for diagnosing prostate cancer. However, early detection and accurate diagnosis of prostate cancer remain challenging. At present, application of diffusion weighted imaging (DWI) is still limited in the PI-RADS scoring system despite its importance as a pivotal sequence. The limitations stem from the conventional DWI’s reliance on long diffusion times, which restrict its detection capabilities to approximately one cell diameter. This limitation results in an assessment of overall tissue diffusion restriction, rather than detailing the micropathological changes within prostate lesions at the intracellular spatial scale. Overcoming this limitation could enhance the early diagnostic accuracy of prostate cancer. In recent years, a novel diffusion MRI technique known as time-dependent diffusion MRI (td-dMRI), has garnered significant interest. Td-dMRI combines oscillating gradient spin echo and pulsed gradient spin echo and utilizes imaging microstructural parameters with limited spectrally edited diffusion model, which is capable of capturing diffusion signals over both short and long diffusion timescales to characterize tissue microstructural changes. It has demonstrated remarkable application potential in the diagnosis and therapeutic realms of various diseases. This article aims to provide a comprehensive review of td-dMRI, and discusses its technical principles, advantages, clinical application value, and the challenges it faces in the context of prostate cancer diagnosis and treatment. Specifically, we will explore its potential for early detection, diagnosis, and management of clinically significant prostate cancer. [ABSTRACT FROM AUTHOR]

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To investigate the effects of the new type middle east Lüjuneng compound fertilizer on the yield, root characteristics and nitrogen absorption and utilization of Wuyunjing 23 rice, the experiments were designed under pot cultivation and field cultivation conditions. Compared with conventional compound fertilizer, the yield of Lüjuneng compound fertilizer was increased in pot experiment and field experiment. The higher the application amount or proportion, the greater the yield increase. The earlier the application, the better the yield increase. Field tests showed that MT5 and HT5 treatment had the best yield increase effect. The increase of yield was mainly due to the significant increase of ear number. The average nitrogen accumulation in maturity stage was increased by 24.9%, and the average nitrogen accumulation in contrast, application and application period was increased by 30.03%, 23.66% and 20.79%, respectively. With the increase of Lüjuneng application rate, nitrogen accumulation showed an increasing trend, and the effect of early application was obviously greater than that of late application. Nitrogen harvest index, nitrogen use rate, nitrogen agronomic use rate and nitrogen partial productivity were all promoted. With the increase of Lüjuneng application rate, the latter three indexes showed an increasing trend. At 30 days after planting, the number of adventitious roots per plant, total length of adventitious roots per plant, root dry weight per plant, total absorbed area and active absorbed area were lower, while the root activity per plant, longest root length and mode root length were higher. At heading stage, the above root characters were higher than control group (CK), but the root-shoot ratio was lower than CK. Root-shoot ratio at maturity was higher than that of CK. The application of Lüjuneng compound fertilizer significantly promoted the increase of ear number, yield and nitrogen use efficiency of rice. [ABSTRACT FROM AUTHOR]

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[Objective]To develop a novel DNA sequencing enzyme that addresses the main challenges faced by first-generation sequencing technology when dealing with complex DNA structure templates, such as interruption of sequencing signals or rapid signal decay. [Method]Taq DNA polymerase and single-strand binding protein SSB gene sequences were mined from the NCBI database, and a novel sequencing enzyme, Sso-Sequenase, was obtained using genetic fusion, site-directed mutagenesis, and gene design techniques. The purified sequencing enzyme was obtained through affinity chromatography and ion exchange chromatography. The performance of Sso-Sequenase was improved using antibody modification technology, and its hot start performance was characterized using STR technology. A variety of complex templates were selected, and the sequencing performance of the Sso-Sequenase sequencing enzyme kit was compared with the traditional BigDye sequencing kit using Sanger sequencing.[Result]Sso-Sequenase was stably expressed in Escherichia coli, with a purity of over 95% and a yield of up to 10.5 mg/L. When the temperature was below 35℃, Sso-Sequenase demonstrated hot-start activity. In first-generation sequencing reactions with complex templates, such as those with repetitive sequences, high GC content, and hairpin structures, Sso-Sequenase successfully completed sequencing for all samples, with an average base quality value QV > 20. In contrast, the BigDye sequencing kit experienced significant signal decay or interruption when processing these complex samples.[Conclusion]A DNA sequencing enzyme, Sso-Sequenase, has been developed to possess exceptional purity, remarkable yield, and hot-start activity. These advancements have significantly bolstered the sequencing success rate for intricate DNA templates, including those characterized by repetitive sequences, high GC content, and hairpin structures. [ABSTRACT FROM AUTHOR]

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血管性认知障碍（vascular cognitive impairment，VCI）患病率逐年增加，现已成为老年人 群中主要的致残原因，但目前尚缺乏有效的治疗手段。近年来磁共振成像技术迅速发展，尤其是功 能影像学，如血氧水平依赖功能磁共振（blood oxygen level dependent functional magnetic resonance i magi ng，BLOD-fMRI）、磁共振波谱技术(magnetic resonance spectroscopy，MRS)、灌注加权成像技术 （perfusion weighted imaging，PWI）等,以其高分辨、非创伤性等优点对患者的脑功能进行评价，为血管 性认知障碍早期识别、鉴别诊断及评估预后等方面提供了影像学依据。 Abstract: The prevalence of vascular cognitive impairment (VCI) is increasing year by year, and it has become the main cause of disability among the elderly. However, there are still in lack of effective treatment. In recent years, magnetic resonance technology has developed rapidly, especially functional imageology, such as blood oxygen level dependent function magnetic resonance imaging (BLOD-fMRI), magnetic resonance spectroscopy (MRS), and perfusion weighted imaging (PWI), which can evaluate the patient’s brain function with the advantages of high resolution, non-traumatic and so on. It provides an imaging evidence for early recognition, differential diagnosis and prognosis evaluation of vascular cognitive impairment, etc.

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