黄绵土不同形态有机氮径流流失规律

利用不同坡度径流小区 ,在自然降水条件下 ,研究侵蚀泥沙不同形态有机氮的流失规律 ,结果表明 :在 4次产流泥沙中 ,除氨基糖氮含量减少外 ,其它有机形态氮均存在增加趋势 ,以氨态氮含量增加最为显著。随坡度的下降 ,水解全氮、氨态氮和氨基酸氮含量呈增加趋势 ;泥沙中水解全氮、氨基酸氮、氨态氮、非酸水解氮均存在不同程度的富集 ,其富集率随坡度的下降而增大 ,以氨基酸氮富集程度高 ,泥沙中氨基糖态氮反而无富集现象存在 ;当坡度分别为 2 5°、2 0°、15°、10°和 5°时 ,水解全氮流失量分别为 1135 .0、76 3.7、485 .5、313.0和 15 4.4kg/ km2 ,而氨基酸氮流失量则为 2 34.8、182 .7、12 1.1、76 .8和 33.9kg/ km2 ,占水解全氮的 2 0 .6 %～ 2 4.9%。氨态氮流失量为 742 .5、5 0 3.3、32 2 .2、2 0 8.9、97.4kg/ km2 ,占水解全氮的 6 3.1%～ 6 6 .7%。氨基糖氮占酸水解氮 1.1%～ 2 .9%。非鉴别氮占水解全氮的 5 .8%～ 12 .6 %。而酸水解氮与非酸水解氮之比分别为 ...

A {Co-32} Nanosphere Supported by p-tert-Butylthiacalix[4]arene

Calixarene-capped Co-32 clusters are constructed by a sodalite Co-24(II) cage and an encapsulated Co-8(III) cube. The spherical units are arranged into three isomeric structures, two of which are stacked by the bcc lattices and the third of which is assembled by the cubic closest packing of the spherical units.

SUPERCONDUCTIVITY IN BI1.5PB0.4SBXSR2CA2CU2OY SYSTEM (X=0-0.32)

The effect of doping with various amount of Sb (0.06-0.32) to (Bi,Pb):Sr:Ca:Cu = 1:1:1:1 system were studied with XRD and Tc measurements. The presence of Sb promotes the conversion of low Tc phase (2212 phase) to high Tc phase (2223 phase) and at around Sb = 0.18 the 2212 phase nearly completely disappears; but at the same time a new phase of unknown structure appears even with Sb = 0.06 showing that the incorporation of Sb into the Bi-based superconducting phase is of very low concentration. Tc measurements show that the optimum concentration of Sb-doping is around 0.10 and that unknown phase has an adverse effect to the superconducting properties; a composition disproportion at the surface of pellet was observed.

Cr-39 A New Alpha-Particle Sensitive Polymeric Detector Applied To Investigations Of Environmental-Radioactivity

Some advantages of a new dielectric detector, CR-39, are described in relation to the analysis of concentrations and distributions of α-particle emitters from a variety of materials. The detector provides an economic and versatile approach to many problems and complements conventional methods of analysis.

New records of interesting xenophytes in the Iberian Peninsula. V

As a continuation of previous research on the naturalization of non-native vascular plants in the Iberian Peninsula new chorological data are presented for 16 xenophytes recorded between 2010 and 2014, mostly in the provinces of Huelva and Barcelona (Spain) and in the Algarve and Estremadura (Portugal). For each taxon details about distribution, habitats occupied, previous records, degree of naturalization, etc. are provided. Lachenalia bulbifera and Cyperus albostriatus are probably reported for the first time in the wild in Europe, as are Gamochaeta filaginea, and Dysphania anthelmintica and Oenothera lindheimeri for Portugal and Spain respectively. Cosmos bipinnatus is cited as a novelty for the Algarve (Portugal). Newly reported or confirmed for the province of Huelva are: Amaranthus hypochondriacus, Epilobium brachycarpum, Nephrolepis cordifolia, Ficus microcarpa, Tamarix parviflora and Tamarix ramosissima, while Atriplex semibaccata, Chloris truncata, and Elymus elongatus subsp. ponticus are new for Barcelona. Finally, Passiflora caerulea is a novelty for both Barcelona and Huelva provinces.

De la cooperativa agroalimentaria a la "learning netchain". Hacia un planteamiento teorico interorganizativo e interpersonal

Se propone un planteamiento teórico/conceptual para determinar si las relaciones interorganizativas e interpersonales de la netchain de las cooperativas agroalimentarias evolucionan hacia una learning netchain. Las propuestas del trabajo muestran que el mayor grado de asociacionismo y la mayor cooperación/colaboración vertical a lo largo de la cadena están positivamente relacionados con la posición horizontal de la empresa focal más cercana del consumidor final. Esto requiere una planificación y una resolución de problemas de manera conjunta, lo que está positivamente relacionado con el mayor flujo y diversidad de la información/conocimiento obtenido y diseminado a lo largo de la netchain. Al mismo tiempo se necesita desarrollar un contexto social en el que fluya la información/conocimiento y las nuevas ideas de manera informal y esto se logra con redes personales y, principalmente, profesionales y con redes internas y, principalmente, externas. Todo esto permitirá una mayor satisfacción de los socios de la cooperativa agroalimentaria y de sus distribuidores y una mayor intensidad en I+D, convirtiéndose la netchain de la cooperativa agroalimentaria, así, en una learning netchain.

Cooperativism, entrepreneurship and economic development: a linking theoretical model

Cooperatives, as a kind of firms, are considered by many scholars as an remarkable alternative for overcoming the economic crisis started in 2008. Besides, there are other scholars which pointed out the important role that these firms play in the regional economic development. Nevertheless, when one examines the economic literature on cooperatives, it is detected that this kind of firms is mainly studied starting from the point of view of their own characteristics and particularities of participation and solidarity. In this sense, following a different analysis framework, this article proposes a theoretical model in order to explain the behavior of cooperatives based on the entrepreneurship theory with the aim of increasing the knowledge about this kind of firms and, more specifically, their contribution to regional economic development.