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91.
辅齿姬蜂属Yamatarotes Uchida主要特征是:唇基端半部平坦,且薄,端缘不具齿;盾纵沟强壮,且平行地伸展至中胸盾片中部消失;肘间横脉位于第2迴脉内侧,两者间距小于肘间横脉长;后足跗爪内侧具小齿;腹部第1节腹板隆肿具直立的毛。 相似文献
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花萼钟状,5裂达基部;裂片条形。花冠白色或淡紫色(?);筒近筒形或漏斗状筒形;檐部二唇形,比简短,上唇正三角形或近半圆形,不分裂,下唇3浅裂。能育雄蕊2,位于下侧方,伸出;花丝着生于花冠简近中部或稍超过中部处,狭条形,直,有1脉;花药基着,宽卵形或长圆形,在腹面顶端连着或分离,药室平行,顶端不汇通。退化雄蕊或存在,3,位于上方,小,或不存在。花盘低杯状。雌蕊内藏;子房条形,2侧膜胎座不内伸,2裂,裂片极叉开,生有胚珠;花柱比子房短,柱头小,扁头状,与花柱等宽或比花柱稍 相似文献
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利用细菌脱除金、锡和铜精矿中砷的研究 总被引:1,自引:1,他引:0
本文报道用从毒砂矿酸性水中分离得到的氧化毒砂和对砷毒害耐受力高的氧化亚铁硫杆菌(Thiobacillus ferrooxidans)C-3菌株,进行浸出砷的试验结果。以毒砂矿物形态存在的砷,主要是在细菌直接氧化下溶出的。影响细菌浸出砷的因素较多,其中精矿含砷量的高低是关键因素。含砷量为11.94%的金精矿,当矿浆浓度为10%时,采用两次浸出,砷的脱除率仍可达70%以上。 相似文献
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A search for source leaf sucrose pools that differed in their relation to export was carried out in photosynthesizing leaves of Beta vulgaris L. The time course of depletion of [14C]sucrose in a leaf in unlabeled CO2 following steady state labeling provided evidence for two distinct sucrose pools. After the start of the light period, leaf blade sucrose remained constant although it exchanged between the two pools. Newly synthesized sucrose destined for export passed through one pool more rapidly than through the other. All of the leaf blade sucrose appeared to exchange with export sucrose. Modeling and regression analysis of [14C]sucrose data provided a means for estimating the size of the two pools. From 20 to 40% of the sucrose was calculated to be present in the pool that provided the less direct path to export; this was likely vacuolar sucrose. The remainder of the sucrose in the blade was probably in the cytoplasm and veins. Added amounts of leaf blade sucrose, produced in response to elevated CO2, appeared to be stored mainly in the vacuolar compartment. 相似文献
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A warm (20 to 15 Celsius day or night) preconditioning treatment enhanced cold acclimation of Cornus stolonifera bark under short-day conditions when plants were preconditioned for at least 4 weeks. Warm preconditioning inhibited the acclimation of plants subjected to long photoperiods. Removing leaves from plants exposed to low temperatures and short days inhibited acclimation. Removal of buds did not affect acclimation. Plants did not acclimate unless they were exposed to at least 4 weeks of short photoperiods prior to defoliation. Plants began to acclimate to cold at the time of growth cessation but not before. When half of the leaves were removed from plants, the defoliated and foliated branches both acclimated as well as branches on completely foliated plants. Girdling the phloem between foliated and defoliated branches prevented acclimation of the latter regardless of the position of the girdle in relation to the root system and the defoliated branch. When all of the leaves of plants were covered with aluminum foil to exclude light after 0 or 4 weeks of exposure to short days, the results resembled a defoliation study, i.e., plants with leaves covered at the start of the experiment failed to acclimate, and those covered after 4 weeks acclimated to some extent but less than uncovered control plants. Under longday conditions plants with all leaves covered failed to acclimate, and plants with none or half of their leaves covered acclimated equally and to a limited extent. Under short-day conditions, however, the covered branches of partially covered plants acclimated more than their uncovered counterparts or branches of totally uncovered plants. 相似文献
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