审计师规模与审计质量：声誉视角

本文基于2010年至2013年的四个公司舞弊事件，考察了声誉受损后的审计师变更情况，发现：市场并没有用“及时离开”来惩罚声誉受损的审计师，使其失去准租，审计师的执业资格直接决定了其能否继续获取准租。我们的讨论，是对DeAngelo（1981b）审计师规模与审计质量的补充与修正，将有助于更好地理解审计师规模与审计质量之间的传导机制，丰富规模与质量的理论体系。本文受国家自然科学基金项目（71672159;71272079）支持

尿素除草活性的培养箱实验

以8种杂草为对象,通过培养箱试验研究不同浓度的尿素溶液对供试杂草萌发及根茎生长的影响。供试草种分别为鬼针草(bIdEnS bIPInnATA)、杂三叶(TrIfOlIuM HybrIduM)、马蹄金(dICHOndrA rEPEnS)、一点红(EMIlIASOnCHIfOlIA)、水蜈蚣(kyllIngA brEVIfOlIA)、狗尾草(SETArIAE VIrIdIS)、高羊茅(fESTuCA ArundInACEA)、多年生黑麦草(lOlIuM PErEnnE)。结果表明,尿素除对狗尾草的萌发无明显抑制作用外,对其他杂草的萌发、根长、茎长均有明显的抑制作用,并随着尿素溶液浓度的增高抑制作用增强,且以对根长的抑制作用最为明显。尿素对供试草种的萌发和根茎生长的抑制作用存在明显的种间差异,对尿素胁迫最敏感的是三叶草和水蜈蚣,然后分别是鬼针草、一点红、高羊茅、马蹄金、多年生黑麦草,最不敏感的是狗尾草,较低浓度的尿素处理反而促进了狗尾草的萌发。深圳市科技计划项目“深圳市草坪杂草——短叶水蜈蚣的生物学特性及无公害防治技术研究”(编号:2007K158BA

Study on subsurface damage depth and morphology of optical elements

根据化学蚀刻法,提出了一种光学元件亚表面损伤的检测方法,分别观测了磨削和抛光后k9玻璃蚀刻后的亚表面损伤。研究表明:光学元件磨削亚表面损伤在光学显微镜下的表现形式为弹坑状缺陷和脆性裂纹;光学元件抛光后也产生了亚表面缺陷,其在AfM下的表现形式为细长条纹状划痕。In this paper,a detection way of subsurface damage in optical elements was put forward based on the chemical etching method.After grinding and polishing,we observed the subsurface damage of K9 glass under different etching time.The study indicates that the manifestations of the grinding subsurface damage under optical microscope are crater-like defects and brittle cracks;the optical elements also has subsurface damage after polishing,and the polishing subsurface damage under AFM manifests as slender striped scratches.国家自然基金项目(51275433); 福建省自然科学基金项目(2010J05122

Research on Detection of Subsurface Damage on Grinding Optical Elements

基于氢氟酸刻蚀对光学元件亚表面裂纹影响的刻蚀模型,将化学刻蚀、逐层抛光技术和激光共聚焦扫描技术相结合,提出了一种磨削加工光学元件亚表面损伤的检测方法。实验证实该方法得到的亚表面损伤深度与公认的亚表面损伤预测模型的预测结果吻合性较好,是一种可靠的亚表面深度检测方法。Based on the etching model which hydrofluoric acid etching has an impact on the subsurface cracks of the optical elements, combined chemical etching, step-by-step polishing techniques and confocal laser scanner,a method of detecting sub-surface damage of the optical element was proposed.Research shows that this detection method is intuitive and effective,and the depth of subsurface damage match with the grinding results predicted by the model.国家自然科学基金(51275433); 福建省自然科学基金(2012J05098

早期糖尿病视网膜病变中eEF2K活性变化的实验观察

目的观察早期糖尿病大鼠视网膜中真核生物延伸因子2激酶(e EF2K)的变化,探讨e EF2K活性变化在早期糖尿病视网膜病变(DR)中的意义。方法建立SD大鼠链脲佐菌素(STZ)糖尿病高血糖模型,造模成功后,设立糖尿病大鼠(DM)组和正常对照(NC)组。qRT-PCR检测DM组和NC组4周和8周时大鼠神经视网膜中e EF2K的表达情况。免疫荧光法观察定位神经视网膜中e EF2K激活标志物-磷酸化真核生物延伸因子2(p-eEF2)和Müller细胞活化标志物胶质纤维酸性蛋白(GFAP)表达情况。结果 4周和8周时DM组大鼠神经视网膜中e EF2K的表达水平与NC组相比无明显变化。8周时DM组大鼠神经视网膜各层均出现e EF2K激活表现,即p-eEF2表达增强。神经节细胞层出现细胞凋亡样改变,凋亡样神经节细胞中e EF2的磷酸化水平增强最为明显。神经视网膜中Müller细胞活化,GFAP蛋白表达增强。结论 STZ诱导糖尿病大鼠早期视网膜病变中神经视网膜内e EF2K激活,在凋亡样神经节细胞中e EF2K活性上升最为显著。福建省自然科学基金项目(2016J 01412);;国家自然科学基金青年项目(81700864

Use of Ammonia-releasing Compounds for Plant Protection

近年来很多研究发现,合理地施用氨释放物不仅能够为植物提供必需的营养元素,而且对植物病害、杂草有很好的防治作用。鉴此,综述了氨释放物在植物保护中防治根结线虫、病原真菌和杂草方面的研究应用状况,并探讨了其相关机制。In recent years,many studies found that a reasonable application of ammonia releasing compounds not only provided necessary plant nutrients,but also had a good control effect on plant diseases and weeds.This paper reviews the use of ammonia releasing compounds for controlling root-knot nematodes,pathogenic fungi and weeds and explores its relevant mechanisms.深圳市科技计划项目(2007K158BA

Effect of three herbicide application in combination with urea on herbicidal activity on turf weeds

以细叶结缕草草坪中4种常见杂草为对象,通过盆栽试验研究3种草坪除草剂草坪隆5号、金百秀、秀白宫与尿素混用对供试草种鬼针(bIdEnS PIlOSA)、三叶草(TrIfOlIuM HybrIduM)、马蹄金(dICHOndrA rEPEnS)、狗尾草(SETArIA)萌发及幼苗生长的影响。结果表明,与尿素混用显著增强了3种草坪除草剂抑制杂草萌发、根芽生长的生物活性,且随着尿素浓度的增加而增效加强。在各处理中,3种除草剂的除草活性为:除草剂+1.0%尿素>除草剂+0.5%尿素>单施除草剂(最大田间使用量)>单施除草剂(1/2最大田间使用量)。同时,尿素对除草剂的增效在除草剂和杂草之间存在差异。This paper evaluated the joint effect of three turf herbicides and urea on herbicidal activity on 4 selected turf weeds through potted experiments.The weed species were Bidens pilosa,Trifolium hybridum,Dichondra repens,Setaria,which were common weeds in Zoysia tenuifolia.The results revealed that herbicide application in combination with urea solution performed better than use of herbicide alone in inhibiting germination,root and shoot development of all tested weed species,and the strengthen effects significantly increased with the urea concentration.Among all treatments,the herbicidal activity order was herbicide+1.0% urea> herbicide+0.5% urea> herbicide(at maximum field application rate) > herbicide(at 1/2 maximum field application rate).There were differences among fertilizer and weed species in the strengthen effects of urea.深圳市科技计划项目(2007K158BA

Subsurface damage of ground optical elements

对磨削加工的k9材料试件进行亚表面损伤探究,分析磨削加工产生亚表面损伤的原因。分别用亚表面损伤深度预测法、分阶刻蚀法预测和检测元件亚表面损伤深度,并分析切深、工作台进给速度、砂轮转速等参数对亚表面损伤深度的影响。研究表明,分阶刻蚀法直观有效,与亚表面损伤深度预测法的结果一致性较好。在本文实验条件下,自行加工k9试件的亚表面损伤深度随切深增大而加深,随工作台进给速度增大而有所增加,砂轮转速对亚表面损伤深度影响并不明显。The subsurface damage of ground K9 specimens and the damage mechanism are studied in this paper.Subsurface damage prediction method and step-by-step etching method are used to measure subsurface damage depth.In addition,cutting depth,feed rate and wheel speed are discussed about the influences on subsurface damage depth.Studies show that,step-by-step etching method is intuitive and effective.For the K9 specimens ground by ourselves,under the experimental conditions in this paper,subsurface damage depth will increase with cutting depth getting deeper or when the feed rate increases.However,wheel speed has no specific influence on subsurface damage depth.“高档数控机床与基础制造装备”国家科技重大专项(2013ZX04006011-206

Research on optical surface quality based on the monitoring of acoustic emission signals

基于声发射检测技术,通过研究磨削光学元件产生的声发射信号的频谱特征,研究其与表面粗糙度之间的关系,从而提出一种光学元件表面质量的判断方法,即一定范围内,光学元件表面质量随着声发射信号能量的增大而降低。由此获得一种快速、实时、便捷和安全的光学元件表面加工质量的检测方法,可用于光学元件表面加工质量的在线生产监控。Based on acoustic emission( AE) testing technology,through researching spectrum characteristic of acoustic emission signals from grinding the optics,research it's relation with surface roughness,provides a method judging the surface quality of optics,thus in a certain range,the quality of optical surface decreases with the increase of AE energy.It is concluded that energy analysis of acoustic signals is feasible for detecting the optical surface quality on line which have the merit of being sensitive,real- time,convenient and safe