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1.
化学药剂预处理对金盏菊蕾期切花保鲜效果的影响   总被引:7,自引:0,他引:7  
探讨了8HQ,AgNO3等化学药剂处理对金盏菊切花瓶插期间水份平衡,可溶性糖含量和过氧化物酶活性的影响,各种药剂处理均可提高观赏品质,其中8-HQ+AgNO3+蔗糖的组合效果最佳,花径增大2.2cm,花重增大49.72%,瓶插寿命延长4d,可溶性糖含量和守氧化物酶活性是导致切衰老的两个重要因素。  相似文献   

2.
UASB反应器处理低浓度有机废水的机理研究   总被引:10,自引:1,他引:10  
研究了6.5LUASB反应器在常温下处理低浓度有机废水的启动、运行和基质降解动力学.研究表明:当污水水温大于15℃时,运行20d后出现颗粒污泥,46d基本上完成反应器的启动.在水温为15~29℃下运行,水力停留时间在3~8.7h,COD去除率可达71.9%~88.5%.对反应器建立基质降解动力学模型,在平均温度为17.2℃,22.3℃和26.4℃下减速增长速度常数K2分别为1.89×10-3,2.40×10-3和2.77×10-3L/mgVSS·d.  相似文献   

3.
将武昌罗索线虫寄生前期幼虫贮存于0-5℃条件下,其有效率分别是:3d为90.5%;6d为86.8%;9d为81%;12d为78%;15d为67.5%;21d为31.3%;27d为26%,蚊幼虫的寄生率分别是:3d为93%;6d为92%;9d为93%;12d为90%;15d为82%;21d为63.5%;27d57%,经方差分析,其有效率在12D之间无显著性差异。Q  相似文献   

4.
杨君丽 《青海大学学报》1999,17(2):38-39,56
对菜青虫采用不同药剂的防效比较试验,结果:16%中农一号水剂对2 ̄3龄菜青虫的防治效果最高为98.4%,最低为92.02%,适宜稀释倍数为200 ̄250倍。有效期可达7 ̄10d。  相似文献   

5.
乳酸生产菌的选育及发酵的研究   总被引:3,自引:0,他引:3  
以分离到的一株德氏乳杆菌(Lactobacillus delbruckii) 1-1为出发菌株,经紫外线、硫酸二乙酯、亚硝酸钠等诱变剂处理,筛选出一株产乳酸较高的突变株ZL-513,乳酸钙产量由5.8%提高至9.4%。以正交试验为基础对发酵培养基进行优化,采用优化后的培养基发酵 3 d,残糖降至 0.1%以下,乳酸钙产量达 15%。比优化前产酸提高 60%,缩短发酵周期 1d。以质量分数 8%~15%的玉米粉为原料进行发酵,乳酸钙产量分别为10%~18.5%。  相似文献   

6.
海南岛美洲斑潜蝇生物学特性及其防治研究   总被引:1,自引:0,他引:1  
通过室内饲养观察和田间系统调查,研究了海南岛美洲斑潜蝇的生物学特性,并采用干扰作用控制指数(IPC)评价了几种杀虫剂对美洲斑潜蝇种群的控制作用.结果表明:1)该虫在海南年发生19~20代,卵历期2~4d,幼虫历期3~7d,蛹历期7d,成虫寿命在15d左右;2)1.8%集琦虫螨克和1%农哈哈对美洲斑潜蝇种群控制效果较好,其干扰作用控制指数分别为0.116和0.111;而98%的巴丹对美洲斑潜蝇种群控制效果较差,IPC值为0.246;40%的氧化乐果的控制效果最差,IPC值为0.301  相似文献   

7.
“926”植物生长调节剂在花生上的药效试验   总被引:1,自引:0,他引:1  
试验了“926”植物生长调节剂在花生上的增产效果,结果表明:喷施80ppm的药剂,平均亩产112-242.8kg,增产率为18.30-23.57%,增产幅度非常显著。  相似文献   

8.
增效剂在某磷矿浮选中的应用研究   总被引:1,自引:0,他引:1  
在磷矿石反浮选中,增效剂KS和TS均对捕收剂油酸具有协同效应,仅采用一粗一精的流程,就可使磷精矿P2O5品位分别达到34.89%和34.80%,与单独使用油酸相比,精矿P2O5中的品位提高了4%以上,药剂成本仅增加0.80 ̄9.00元/t,初步讨论了增效剂作用机理。  相似文献   

9.
应用48%地乐胺药剂防除密植型蔬菜韭菜、胡萝卜田间杂草,简便易行。试验结果表明:使药期在幼苗未出土或刚出土(播后大约10~15d),灌水后于地表喷施,防除效果达95%。最佳使用量为3000~3750ml/hm2,每公顷药液1200~1500kg,用药量超过4500mg/hm2,有药害产生。  相似文献   

10.
本文研究并比较了在硼砂介质中,苯酚及其衍生物的电化学行为,利用本酚在—0.5V(对SCE)吸附富集,再进行氧化溶出,建立了测定苯酚的新方法。该法简单、灵敏,苯酚的检测限为8×10-8mol.L-1,浓度在5×10-7~8×10-6mol.L-1范围内与溶出峰电流ip呈良好的线性关系。对用酚醛树脂涂料马口铁制成的蕃茄酱罐头中苯酚的测定,回收率在84.6%~89.5%之间。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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