Is the jet of AO 0235+164 rotating?

We present the VLBI map of a superluminal radio source AO 0235+164 at 5 GHz. This shows that the object's radio structure is dominated by a strong, nearly unresolved core with two extended asymmetric weak jet components. Based on the variation of its flux density with time at 5 GHz, we suggest that the flux density of AO 0235+164 exhibits two periodic variations: a shorter-period variation of 1.81±0.06 yr and a longer-period one of 3.64±0.08 yr. These two periodic variations could be the result of the joint action of jet outbursts and jet rotation.     

盐湖卤水数据采集系统中的通信方法

介绍了盐湖卤水动态自劝观测系统中单片机数据采集系统与智能测钾仪及智能水位计之间的通信。前者来用并行通信，后者采用串行通信．分别介绍了两种通信方式的硬件接口和程序设计。     

射电天文台址电子设备电磁辐射评估

射电望远镜具有极高的系统灵敏度,且系统内、系统间及台址内电子设备众多,电磁环境复杂,科学合理地评估台址内电子设备辐射发射对射电天文观测的影响,对系统电磁兼容性设计、无线电管理、屏蔽改造等有重要的指导意义。浅析了射电望远镜系统灵敏度及射电天文领域仪器设备辐射发射相关评估标准;基于射电望远镜系统灵敏度及观测需求,计算了南山25 m射电望远镜馈源口面干扰电平限值,并给出了天线旁瓣增益的计算方法;提出一种基于干扰电平限值、旁瓣增益、干扰测量、路径衰减的电子设备电磁辐射评估方法,并针对南山25 m射电望远镜天线驱动电磁辐射进行了评估,给出了屏蔽需求。     

CHARACTERISTICS OF ZONAL ANOMALY OF ANNUAL PRECIPITATION IN THE NORTHEASTERN CHINA

The characteristics of zonal anomaly and change rule of temporal distribution of annual precipitation in the northeastern China are revealed in this paper with EOF (Empirical Orthogonal Function) and REOF (Rotated Empirical Orthogonal Function) methods and results are drawn in the standard relief maps with GIS technology for practical application. Data used in the study were obtained from 208 meteorological stations over the northeastern China from 1961 to 2001. EOF results show that the first 3 loading vectors could give entire spatial anomaly structure of annual precipitation. In the Northeast Plain including the Songneng Plain and the Liaohe Plain, there is a regional compatibility (whether wet or dry) of annual precipitation change and this precipitation pattern has occurred since the late 1980s to the present. There also exist annual precipitation patterns of wet (or dry) in south and dry (or wet) in north and wet (or dry) in east and dry (or wet) in west. REOF results display 8 principal precipitation anomaly areas by the first 8 rotated loading vectors: the west plain, the Liaodong hills, the Sanjiang Plain, the Liaoxi hills,the Changbai Mountains, the Hulun Buir Plateau, the southwest plateau and the Liaodong Peninsula.     

从资源、区位和市场看番禺市旅游发展定位

番禺市的旅游资源、旅游区位和交通条件,以及客源市场潜力在珠江三角洲乃至广东省都占有十分重要的地位。其旅游发展应定位于以观光旅游为基础,大力发展娱乐旅游和商务旅游,策略吸引珠江三角洲的家庭游客和商务游客。     

Seasonal variation of airborne fungi of the Tiantishan Grottoes and Western Xia Museum,Wuwei, China

In this study, a systematic survey of cultural airborne fungi was carried out in the occurrence environments of wall paintings that are preserved in the Tiantishan Grottoes and the Western Xia Museum, China. A bio-aerosol sampler was used for sampling in four seasons in 2016. Culture-dependent and -independent methods were taken to acquire airborne fungal concentration and purified strains; by the extraction of genomic DNA, amplification of fungal ITS rRNA gene region, sequencing, and phylogenetic analysis, thereafter the fungal community composition and distribution characteristics of different study sites were clarified. We disclosure the main environmental factors which may be responsible for dynamic changes of airborne fungi at the sampling sites. The concentration of cultural airborne fungi was in a range from 13 to 1,576 CFU/m³, no significant difference between the two sites at the Tiantishan Grottoes, with obvious characteristics of seasonal variation, in winter and spring were higher than in summer and autumn. Also, there was a significant difference in fungal concentration between the inside and outside of the Western Xia Museum, the outside of the museum was far more than the inside of the museum in the four seasons, particularly in the winter. Eight fungal genera were detected, including Cladosporium, Penicillium, Alternaria, and Filobasidium as the dominant groups. The airborne fungal community structures of the Tiantishan Grottoes show a distinct characteristic of seasonal variation and spatial distribution. Relative humidity, temperature and seasonal rainfall influence airborne fungal distribution. Some of the isolated strains have the potential to cause biodeterioration of ancient wall paintings. This study provides supporting information for the pre-warning conservation of cultural relics that are preserved at local sites and inside museums.     

国内价值链构建下地方产业集群升级机理研究

承接产业转移是广大中西部地区的重大发展机遇。在分析全球价值链(GVC)的基础上,立足于我国经济梯度,提出了构建国内价值链(NVC)的基本思路。根据劳动力、资源、市场和区位等不同要素,明确了国内价值链主要划分为生产者驱动价值链、购买者驱动价值链、原材料驱动价值链和混合驱动价值链4种形式,重点分析了在不同价值链下地方产业集群升级的重点和方向,提出了不同的地方产业集群升级模式和内在机理。     

Salinivibrio sp.YH4胞外丝氨酸蛋白酶EYHS耐盐性及生物信息学分析

摘要：目的 探讨菌株Salinivibrio sp.YH4分泌的丝氨酸蛋白酶EYHS的耐盐性及结构特征。方法 明胶底物酶谱法分析EYHS的耐盐性。应用生物信息学手段对EYHS及6种耐盐的S8家族丝氨酸蛋白酶结构特征进行分析。结果 EYHS在4 mol/L的NaCl溶液中仍具有活性,属于耐盐蛋白酶。EYHS及6种S8家族丝氨酸蛋白酶分子表面的loop区等无规则卷曲所占比例较高,α-螺旋与β-片层则主要位于酶分子内部。EYHS分子表面酸性氨基酸含量较高,且具有弱疏水内核。多序列比对发现蛋白酶的催化三联体两侧存在高度保守的基序和保守的极性氨基酸及芳香族氨基酸,并存在多个保守的Gly与Ala。同源模建和表面电荷分布显示,α螺旋和β片层围成了蛋白酶的催化腔,EYHS活性中心包含由Asp32、His65与Ser215组成的催化三联体,且催化位点区域表面静电势为负。结论 上述结构特征可能有助于耐盐丝氨酸蛋白酶EYHS在高盐环境下维持其稳定性和适度柔性,并有助于其催化功能的发挥,为深入研究耐盐丝氨酸蛋白酶的高盐环境适应性提供了一定的理论依据。     

中国留学人员创业园分布及产业特征

以《中国留学人员创业年鉴》为基础数据,采用GIS空间分析技术,运用核密度估计法、L函数和最近邻层次聚类分析等方法,分析2006~2015年中国留学人员创业园空间分布规律以及园区产业集聚特征,结果表明：中国留学人员创业园集聚特征显著,而且随着时间的推移,其多中心趋势明显,集聚规模迅速增大,集聚强度呈“先升后降,但总体增大”趋势;主要集聚于长三角、京津冀和珠三角等地区,尤以前两者最显著,且三大集聚区的集聚强度与集聚规模差异明显,其中长三角留创园的集聚规模最大,京津冀集聚强度最高,而珠三角则比较复杂,其在很小空间尺度范围内服从集聚分布,而在较大空间尺度范围内则服从随机分布;基于不同主导产业的中国留学人员创业园依然集中于长三角、京津冀和珠三角等地区,其主导产业分布格局则差异显著,规律性不强。     

中国第26次南极考察南大洋碳通量评估

南大洋是大气CO2的重要汇区,而近几十年来这个汇出现了明显变化并成为了研究的热点。利用中国第26次南极考察期间雪龙船绕南极航行所获得的现场碳及相关参数观测数据,分析推导出海水pCO2及其主控因子(叶绿素和水温)之间的经验关系,并结合相关卫星遥感数据建立遥感外推算法,计算南大洋50°S以南海区碳通量分布,评估该海区对大气CO2的吸收能力。计算结果表明,2009年11月从90°E到90°W(顺时针方向),50°—75°S海域为CO2输送大气的弱源,平均输入大气通量为9.482 mol·m-2·month-1,碳释放量为0.001 779 5×1015gC;2009年12月从90°W—90°E(顺时针方向),50°—75°S海域为吸收大气CO2的弱汇,平均碳通量为-12.451 mol·m-2·month-1,碳吸收量为0.026 656×1015gC。将经验关系推导至该月份的50°—75°S整个南大洋的计算中发现,2009年11月南大洋为大气CO2的源,碳释放量为0.002 789 6×1015gC;在2009年12月南大洋为大气CO2的汇,碳吸收量是-0.003 503 5×1015gC。相比之前我们所观测的结果,南大洋的碳汇吸收能力呈现明显下降。