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41.
Xiaoming Li Xiaopeng Duan Jiawei Qiao Shilin Li Yunhao Cai Jianqi Zhang Yuan Zhang Xiaotao Hao Yanming Sun 《Liver Transplantation》2023,13(1):2203044
The power conversion efficiencies (PCEs) of all-polymer solar cells (all-PSCs) have already exceeded 17%. However, the limited absorption range of an all-polymer system results in significantly reduced short-circuit current density (Jsc), which eventually influences the PCE improvement. To broaden the light absorption of polymer acceptors, herein, benzotriazole is introduced in the core unit of small molecule acceptors and thus two narrow-bandgap polymer acceptors named PTz-BO and PTz-C11 featuring the same molecular backbone and different side-chain length are synthesized. Compared with PTz-C11, the PTz-BO based-all PSCs deliver a slightly reduced Jsc, a large open-circuit voltage (Voc) and a low voltage loss below 0.50 V. Moreover, ternary all-PSCs are constructed by introducing PTz-C11 as a guest component. Benefiting from the reduced recombination, improved exciton generation and dissociation, and balanced charge transport, a high efficiency of 16.58% is obtained for the ternary all-PSCs, with a high Jsc over 25 mA cm−2 without sacrificing the Voc. Such result represents the highest efficiency reported for benzotriazole-based all-PSCs in the literature thus far. This work demonstrates the great potential of benzotriazole for the synthesis of efficient narrow-bandgap polymer acceptors. 相似文献
42.
Ye Wang Yong-Hui Xie Qin-Hong Jiang Hong-Tao Chen Rui-Hao Ma Zhi-Jiang Wang Mei-Zhen Yin Jie Shen Shuo Yan 《Insect Science》2023,30(1):2-14
The unscientific application of synthetic pesticides has brought various negative effects on the environment, hindering the sustainable development of agriculture. Nanoparticles can be applied as carriers to improve pesticide delivery, showing great potential in the development of pesticide formulation in recent years. Herein, a star polymer (SPc) was constructed as an efficient pesticide nanocarrier/adjuvant that could spontaneously assemble with thiocyclam or monosultap into a complex, through hydrophobic association and hydrogen bonding, respectively, with the pesticide-loading contents of 42.54% and 19.3%. This complexation reduced the particle sizes of thiocyclam from 543.54 to 52.74 nm for pure thiocyclam, and 3 814.16 to 1 185.89 nm for commercial preparation (cp) of thiocyclam. Interestingly, the introduction of SPc decreased the contact angles of both pure and cp thiocyclam on plant leaves, and increased the plant uptake of cp thiocyclam to 2.4–1.9 times of that without SPc. Meanwhile, the SPc could promote the bioactivity of pure/cp thiocyclam against green peach aphids through leaf dipping method and root application. For leaf dipping method, the 50% lethal concentration decreased from 0.532 to 0.221 g/L after the complexation of pure thiocyclam with SPc, and that decreased from 0.390 to 0.251 g/L for cp thiocyclam. SPc seems a promising adjuvant for nanometerization of both pure and cp insecticides, which is beneficial for improving the delivery efficiency and utilization rate of pesticides. 相似文献
43.
渗透胁迫对高粱根K~+吸收的影响 总被引:4,自引:0,他引:4
以CaSO40.5mmolL-1溶液培养高粱得到低钾植株,在渗透胁迫下当PEG-1000使外界渗透势下降时,刺激了高粱根高K+亲和系统的净K+积累,其表观Km值和Tmax值分别为18μmolL-1和49.6μmolg-1DWh-1。此高亲和系统不受可渗物质乙二醇和外界pH变化的影响,为蛋白质合成抑制剂环己酰亚胺抑制。 相似文献
44.
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46.
神经节苷脂GM_3对小鼠腹腔常驻巨噬细胞(R-M)和Ge-132体内激活的巨噬细胞(Ge-132-M)的磷脂代谢转换有显著的影响,当这两种M在体外用GM_3处理时,表现出[ ̄(32)P]Pi和[ ̄3H]肌醇参入PI降低,参入PIP、PIP_2增加;但在[ ̄(32)P]Pi和[ ̄3H]胆碱参入PC上,R-M与Ge-132-M不同,即GM_3促进同位素前体参入R-M的PC,抑制它们参入Ge-132-M的PC.以上结果表明GM3可能提高了PI或PIP的磷酸激酶的活性,致使[ ̄(32)P]PIP和[ ̄(32)P]PIP_2增多,[ ̄(32)P]PI减少.激活的M(Ge-132-M)本身PC代谢转换率较R-M高,当Ge-132-M再受GM_3刺激,PC代谢转换率降低,这提示GM_3对激活的M的PC代谢转换有调节作用. 相似文献
47.
Summary Xanthate floatation compounds, added to cultures of Thiobacillus ferrooxidans leaching chalcopyrite, inhibited growth in the concentration range 1–10 mM and caused a drop in formation of soluble copper and iron. Maximum (80–90%) growth inhibition was at 10 mM for isobutyl-, amyl- and ethyl xanthate while isopropyl xanthate was innocuous but caused a four-fold increase in lag phase. Copper production was depressed by 30% for isopropyl-, 53% for isobutyl-, ethyl- and 77% for amyl xanthate at 10 mM additions. 相似文献
48.
原生质体电融合酵母多倍体生理特性的研究 总被引:5,自引:0,他引:5
对原生质体电融合技术获得的11株酵母多倍体融合株,进行了一系列生理特性的分析比较.结果发现,在电融合过程中,融合株的细胞体积及DNA含量并不随着核倍性呈线性递增.而是有其特殊的变化规律。当糖化酵母sta1、sta2和sta3在细胞核中各自纯合时,明显表现出表达的剂量效应。其中sta1、sta2纯合的融合株.在YEPS培养中,GA分泌可被淀粉大量诱导,表现出一定的二次生长特性。从分析结果推测,在亲株5301-14D及HU-TY—1A中可能有对GA分泌不利的因素。 相似文献
49.
Christine Heym Brigitta Braun Yin Shuyi Lat's Klimaschewski Mario Colombo-Benkmann 《Histochemistry and cell biology》1995,104(3):233-243
Applying a double-labelling immunofluorescence technique, six types of substance P-containing nerve fibres were distinguished in the human adrenal gland according to the immunohistochemical colocalization of (I) calcitonin gene-related peptide (CGRP), (II) cholecystokinin, (III) nitric oxide synthase, (IV) dynorphin, (V) somatostatin, and (VI) vasoactive intestinal polypeptide. Fibre populations I to IV in their mediator content resembled the respective subpopulations of primary sensory neurons in human thoracic dorsal root ganglia, while populations V and VI revealed no correspondence with dorsal root neurochemical coding. Nerve fibres with the combination substance P/nitric oxide synthase occurred only in the adrenal cortex, whereas all other fibre types were present in both cortex and medulla. As revealed by immuno-electron microscopy, substance P-immunolabelled axon varicosities (a) exhibited synaptic contacts with medullary chromaffin cells or with neuronal dendrites, (b) were directly apposed to cortical steroid cells and (c) were separated from fenestrated capillaries only by the interstitial space. These findings provide immunochemical support for an assumed sensory innervation of the human adrenal gland, and additionally suggest participation of substance P in efferent autonomic pathways. Furthermore, the results are indicative for a differentiated involvement of substance P in the direct and indirect regulation of neuroneuronal and neuroendocrine interactions. 相似文献
50.
蓟属两种植物的染色体研究 总被引:2,自引:0,他引:2
本文对蓟属(Cirsium)的两个形态相似的近缘种大刺儿菜和小刺儿菜进行了染色体研究,其中后者为首次报道。观察结果表明:两个种的染色体数目均为2n=2x=34:它们的核型是:大刺儿菜.2n=2x=34=20m+12sm+2st:小刺儿菜.2n=2x=34=22m+10km(2SAT)+2st。通过核型比较,认为它们是两个独立的种.而且后者比前者进化。 相似文献