塔里木河流域淡水养殖业可持续发展思考

淡水养殖业发展一直很稳定,其在渔业经济中的地位不可取代,但随着社会经济的发展,养殖环境和条件也随之发生变化,出现了许多妨碍发展的新情况、新问题。文章就塔里木河流域淡水养殖业的发展状况与存在问题,从加强养殖环境整治和养殖容量研究、实施良种工程和科技兴渔战略、建设病害防治体系、严格规范养殖行为等方面,提出几点有针对性的对策。     

长吻鮠人工高产养殖技术

介绍了长吻鮠的生物学特点,总结了长吻鮠的人工养殖技术,包括池塘养殖条件、鱼种放养、饲料投喂、日常管理和病害防治等内容,以期为长吻鮠的人工养殖提供参考。     

景宁县人工养殖大鲵可行性分析

介绍了景宁县的自然条件概况、大鲵的生物学特征特性及生活习性,分析了景宁县人工养殖大鲵的优势。并指出发展大鲵人工养殖的巨大效益,以期促进景宁县人工养殖大鲵产业的形成与发展。     

无公害水产品8种养殖模式

一、人工生态环境养殖法。即人工创造符合无公害水产品生产环境条件的水域一,选择合适的养殖品种进行无公害养殖。例如,种草养殖虾、蟹,已成为发展无公害虾、蟹养殖,建设大面积生     

美蛙人工养殖技术

通过对美蛙人工养殖进行研究,在工作中积累了一些有助于提高养殖水平和经营效益的经验,从场地条件及蛙池建设、蛙种选择与饲养、幼蛙繁殖、幼蛙饲养与管理、越冬管理等方面总结了美蛙人工养殖技术,以期为美蛙的养殖提供技术参考。     

美蛙人工养殖技术

通过对美蛙人工养殖进行研究,在工作中积累了一些有助于提高养殖水平和经营效益的经验,从场地条件及蛙池建设、蛙种选择与饲养、幼蛙繁殖、幼蛙饲养与管理、越冬管理等方面总结了美蛙人工养殖技术,以期为美蛙的养殖提供技术参考。     

小小蜗牛也能挣大钱

我国蜗牛的人工饲养、繁殖技术多年来在科研人员以及养殖户的不断总结,摸索中已经总结出规模化养殖的成功经验。目前人工养殖蜗牛的主要品种是“中华白玉蜗牛”和“法国散大蜗牛”,均可在我国南北方养殖。 人工养殖蜗牛的环境条件要求很简单,可在楼房、平房室内养殖,地下室、菜窖也可以。在室外开放式养殖,如庭院、林场、果园、荒山、野外坡地效果也很好。蜗牛是杂食性     

岩原鲤生物学特性及驯养技术

通过对岩原鲤生物学特性观察及驯养技术试验,结果:岩原鲤生长适宜温度范围4~36℃,最适生长温度18~30℃,在池塘养殖条件下,投喂人工配合饲料能正常摄食生长,但与其他养殖鱼类相比其生长速度较慢。亲鱼在池塘养殖条件下,能够正常生长发育并达性成熟。表明,岩原鲤在人工养殖条件下,能够正常生长发育成熟,可人工繁殖苗种,进行商品化养殖是可行的。     

大斑芫菁生物学特性及养殖技术研究

通过开展大斑芫菁在实验室条件下人工饲养,观察了其形态特征和生活史等生物学特征,分析了其成虫饲养、卵孵化和幼虫饲养等人工养殖技术,并对大斑芫菁养殖与应用前景进行了展望。     

美洲大蠊若虫人工养殖的研究进展

文章从提高人工养殖条件下美洲大蠊若虫的生产性能出发,分析了人工养殖环境温度、湿度、光照、营养与饲料、病害与天敌防控等因素对改善美洲大蠊若虫养殖效益的影响。     

Structure of the hydrated alpha-Al(2)O(3) (0001) surface

The physical and chemical properties of the hydrated alpha-Al(2)O(3) (0001) surface are important for understanding the reactivity of natural and synthetic aluminum-containing oxides. The structure of this surface was determined in the presence of water vapor at 300 kelvin by crystal truncation rod diffraction at a third-generation synchrotron x-ray source. The fully hydrated surface is oxygen terminated, with a 53% contracted double Al layer directly below. The structure is an intermediate between alpha-Al(2)O(3) and gamma-Al(OH)(3), a fully hydroxylated form of alumina. A semiordered oxygen layer about 2.3 angstroms above the terminal oxygen layer is interpreted as adsorbed water. The clean alpha-Al(2)O(3) (0001) surface, in contrast, is Al terminated and significantly relaxed relative to the bulk structure. These differences explain the different reactivities of the clean and hydroxylated surfaces.     

脱落酸(Abscisic acid, ABA)对映异构体的生物活性比较

 采用新方法精制脱落酸(ABA)异构体试样,改变以往靠光学离析法分离racemic型(SR)-(±)-ABA,提高了(S)-(+)-ABA与(R)-(-)-ABA两镜像体纯度。抑制生长试验和残留量分析结果表明:天然型(S)-(+)-ABA活性,显着高于非天然型(R)-(-)-ABA或(SR)-(±)-ABA活性。抑制莴苣种子发芽50%的活性强度(S)-(+)-ABA约是(R)-(-)-ABA的5倍,(SR)-(±)-ABA介于二者之间。抑制萝卜下胚轴生长试验,最显着有效期2～6天,(6天后差异渐小,8日甚微),生理作用期约为一周,(S)-(+)-ABA活性是(R)-(-)-ABA的3.6倍。差异原因可能是两异构体分子立体结构不同所致。     

山西三点棍腹实蝇和具条实蝇种群动态监测

2006年,于山西的侯马、长治、交城、祁县、太原,在Steiner诱捕器内加T,Cue,Me诱剂诱集各种实蝇,监测山西境内实蝇的发生动态。结果表明,三点棍腹实蝇(Dacus(Callantra)trimacula(wang))和具条实蝇(Bactrocera(Zeugodacus)scutelltat(Hendel))是山西的优势实蝇种群,各诱集点两种实蝇种群动态基本一致,每年的6月底7月初由南到北相继发生,高峰期出现在8月中下旬至9月上中旬,种群消退结束于9月底到10月上旬。两种实蝇一年发生一代,种群羽化整齐。     

Ultrafast mid-infrared response of YBa(2)Cu(3)O(7-delta)

Optical spectra of high-transition-temperature superconductors in the mid-infrared display a gap of in-plane conductivity whose role for superconductivity remains unresolved. Femtosecond measurements of the mid-infrared reflectivity of YBa(2)Cu(3)O(7-delta) after nonequilibrium optical excitation are used to demonstrate the ultrafast fill-in of this gap and reveal two gap constituents: a picosecond recovery of the superconducting condensate in underdoped and optimally doped material and, in underdoped YBa(2)Cu(3)O(7-delta), an additional subpicosecond component related to pseudogap correlations. The temperature-dependent amplitudes of both contributions correlate with the antiferromagnetic 41-millielectronvolt peak in neutron scattering, supporting the coupling between charges and spin excitations.     

The spin excitation spectrum in superconducting YBa(2)Cu(3)O(6.85)

A comprehensive inelastic neutron scattering study of magnetic excitations in the near optimally doped high-temperature superconductor YBa(2)Cu(3)O(6.85) is presented. The spin correlations in the normal state are commensurate with the crystal lattice, and the intensity is peaked around the wave vector characterizing the antiferromagnetic state of the insulating precursor, YBa(2)Cu(3)O(6). Profound modifications of the spin excitation spectrum appear abruptly below the superconducting transition temperature T(c), where a commensurate resonant mode and a set of weaker incommensurate peaks develop. The data are consistent with models that are based on an underlying two-dimensional Fermi surface, predicting a continuous, downward dispersion relation connecting the resonant mode and the incommensurate excitations. The magnetic incommensurability in the YBa(2)Cu(3)O(6+)(x) system is thus not simply related to that of another high-temperature superconductor, La(2-)(x)Sr(x)CuO(4), where incommensurate peaks persist well above T(c). The temperature-dependent incommensurability is difficult to reconcile with interpretations based on charge stripe formation in YBa(2)Cu(3)O(6+x) near optimum doping.     

杨树蛀干性害虫杨大透翅蛾的发生与防治

本文对我国北方杨树蛀干性害虫杨大透翅蛾(Aegerla apiformls clerck)进行了研究。除对形态特征,生活史,生活习性记述外,着重该虫的发生量与营林措施及不同杨树品种的关系,以及一系列的防治试验。在此基础上提出成虫期采用活雌虫性诱;卵期树干涂白;幼虫期使用熏蒸毒签等经济有效的防治手段。同时营造乔灌混交林,选用抗虫性较强的毛白杨等13个品种,可有效地控制该虫的发生量。     

齐口裂腹鱼和重口裂腹鱼消化道形态和组织结构的观察

本文对齐口裂腹鱼和重口裂腹鱼消化道的大体形态及显微结构进行了观察和比较，并探讨了结构与食性的关系。两种鱼消化管分为口腔、咽、食道、肠等四个部分；消化道管壁除口腔、咽外均由粘膜、粘膜下层、肌层和浆膜构成；食道上皮均为复层扁平上皮；肠上皮主要由柱状细胞和杯状细胞组成，其间有嗜酸性颗粒细胞；杯状细胞的数量在前、中肠少，后肠增多；两种鱼在口腔、咽形态组织结构，肠长度和盘曲程度方面差异较大，与其食性密切相关。     

甜菜夜蛾天敌的研究进展

对甜菜夜蛾(Spodoptera exigua Hubner)的天敌种类,包括捕食性天敌、寄生蜂、寄生蝇、病原线虫、微孢子虫、病原真菌、细菌和病毒等及其应用进行了综述,并就当前应用中存在的问题及解决方法进行了探讨.