休谟关于神迹论证的贝叶斯式分析

休谟在《人类理解研究》第十章“论神迹“中,提出了一个反驳神迹的重要原则:“衡量证据“原则,他认为一个神迹只有在存在一组对它有利的证据时才能被建立。通过利用概率统计学上的贝叶斯定理,休谟关于神迹的论证能得到重新解释。无论是对单一神迹的单独证明,还是对众多神迹的联合证明,借助贝叶斯定理都可以得到清楚明白的说明。原则上不管是单一神迹还是众多神迹中至少一个发生的可能性,经过个别证据的累积都可以达到一个高的概率。在给定条件下,对于信仰上帝的人们而言,关于神迹的证据可以为上帝的存在提供有力的支持,但是假如人们不准备做一个信仰者,那么即使他拥有这么多关于神迹的证据,他也仍然没有理由去相信上帝存在

有机磷酸酯在环境/ 生物相中的分布、分析方法及毒理效应

有机磷酸酯(organophosphate esters, OPEs)主要作为阻燃剂及增塑剂等而被广泛使用,且极易释放于环境。近年来,由于溴系阻燃剂的禁用,有机磷酸酯类阻燃剂的产量及消费量大幅增加,OPEs 已经成为一种新兴污染物并受到广泛关注,多篇文献报道了其在环境及生物相中的分布和毒理效应。本文主要对OPEs 在地表水、沉积物、大气及生物相中的分布、分析方法及毒理效应进行综述,并对未来OPEs 分布及毒理学研究进行展望,以期为后续该类物质的研究提供借鉴

Distribution and Seasonal Variations of Chromophoric Dissolved Organic Matter （CDOM） in the Bohai Sea and the North Yellow Sea

UV-Vis spectral data and a fluorescence excitation-emission matrix (EEM) was analyzed for the surface, middle, and bottom layer water samples from the Bohai Sea and North Yellow Sea in April, August, and December of 2016 and February of 2017. Distribution characteristics, influencing factors, and seasonal variation of CDOM in the study area were investigated. The results showed that the horizontal distributions of CDOM are similar in different seasons, showing a characteristic of high levels near shore and low levels in the offshore region. Strong correlations were observed between value a (355) and spectral slope S275-295, indicating that CDOM is significantly affected by land input. According to the vertical distribution, the CDOM level is the lowest in surface seawater in summer due to strong photo-degradation. In February, controlled by primary productivity, the lowest level of CDOM was found in the bottom seawater. From April 2016 to February 2017, the content of CDOM first increased and then decreased. Its concentration was highest in December. Seasonal variations are mainly controlled by land input and on-site production. According to analysis of the spectral slope S275-295, the average molecular weight of CDOM in winter was smallest in February, which was mainly related to the drastic reduction of land-based input at that time. The strong photo-degradation in summer resulted in a small average molecular weight of CDOM

Determination of Phthalate Ester Plasticizers in the Atmosphere of the Yellow Sea

应用气相色谱-质谱联用技术,测定了黄海海洋大气中六种主要邻苯二甲酸酯的浓度。利用加标回收实验、空白实验、穿透性实验以及检出限等措施,保证实验结果的可靠性。对黄海海洋大气中PAEs的污染状况进行了分析。研究结果表明:黄海海洋大气中PAEs总浓度范围为75~311 ng/m3,平均浓度为190 ng/m3。Di BP为主要污染物,平均浓度达161 ng/m3。黄海周边地区释放的污染物对黄海大气中邻苯二甲酸酯的浓度有较大影响

Amino acid composition and its biogeochemistry implications of surface sediments in coastal areas of China

1 引言 氨基酸是大多数生物体有机氮和有机碳的主要组分,也是近代沿海海洋沉积物有机质的重要组成部分~([1])

典型氟工业园周边河流沉积物中全(多)氟化合物的分布特征

采用超高效液相色谱/质谱联用(UPLC/MS-MS)分析了我国重要的氟化物工业园区周边河流———辽宁细河(阜新段)、山东小清河(淄博段)和长江(江苏常熟段)表层沉积物中全(多)氟烷基化合物(PFASs)的污染状况.细河表层沉积物中,PFASs含量范围(以干重计,下同)为15.8~ 2770ng·g~(-1),全氟丁烷磺酸(PFBS)和六氟环氧丙烷二聚酸(HFPO-DA)是主要污染物;小清河表层沉积物中,PFASs含量为12.2~ 7853ng·g~(-1),全氟烷基辛酸(PFOA)和HFPO-DA为主要污染物;长江表层沉积物中,PFASs含量为9.20~ 35.9ng·g~(-1),全氟十四酸(PFTeDA)和6∶ 2氟调磺酸(6∶ 2FTS)为主要污染物.工业园区废水排放(点源污染)是本研究中3个区域PFASs的主要来源.3个区域PFASs含量及组成差异明显,与工业园区生产规模和产业类型有关.PFASs含量及各组分含量与TOC、沉积物粒径没有显著相关性,PFASs各组分间相关性也有差异,说明PFASs在沉积物中的富集过程与多种因素有关

Distribution Characteristics of Per-/polyflouralkyl Substances in River Sediments Around Typical Fluorine Industrial Parks

Perfluoroalkyl and polyfluoroalkyl substances(PFASs)are a group of manmade chemicals and are ubiquitously detected in aquatic environments.China is a major producer and consumer of PFASs.In this study,we investigated the occurrence and characteristics of PFASs in the surface sediments from three fluorine industrial parks in North China,the Xihe River in Liaoning Province(Fuxin Section),the Xiaoqing River in Shandong Province(Zibo Section),and the Yangtze River in Jiangsu Province(Changshu Section),using the UPLC/MS-MS method.The total concentration of PFASs(Sigma PFASs)in surface sediments of the Xihe River ranged from 15.8 to 2 770 ng·g~(-1),and PFTeDA and HFPO-DA were the dominant pollutants.In the surface sediments of the Xiaoqing River,Sigma PFASs ranged from 12.2 to 7 853 ng·g~(-1),and PFOA and HFPO-DA were the dominant pollutants.In the surface sediments of the Yangtze river,Sigma PFASs ranged from 9.20 to 35.9 ng·g~(-1),and PFTeDA and 6∶ 2 FTS were the main pollutants.Sewage discharge from the industrial parks(point source pollution)was the main source of PFASs in three regions in this study.The PFAS content and composition in three regions varied significantly depending on the production capacity and industry type.There was no significant correlation between the content of PFASs and its components and the particle size and TOC of the sediments.The correlations between the components of PFASs indicated that the enrichment process of PFASs in sediments was impacted by various factors

个人信息交换语法(PKCS12)结构分析

个人信息交换语法(PKCS12)在信息安全领域得到了广泛的应用,了解PKCS12的数据结构及其实现将有助于我们了解如何实现对CA证书中各种信息(包括私有信息)的保护,从而使数字证书的随身携带成为可能