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1.
北海道では1980年代から2010年代まで,水稲圃場栽培期間である5–9月の気温は年代とともに上昇した。そこで,直近の2010年代(2010—2019年平均)と比べて, 2つの2030年代の予測気象から,既報の関係式より水稲生育を予測した。その結果,2030年代では2010年代に比べ,限界移植日(移植早限)が水稲栽培17地域の平均で8~9日早い。また,早限出穂期が1~5日早く,晩限出穂期が1~5日遅く,安全出穂期間が2~10日長い。出穂期は1~3日早い。出穂期から晩限出穂まで2~9日長いため,遅延型冷害の発生がやや少ない。生育期別気象は,出穂前24日以降30日間では生育が早いため平均気温が同じかやや低い。出穂前10日以降40日間および出穂期以降40日間では平均気温がやや高く,日射量はやや少ない。そのため,玄米収量は96~98%とやや低く,潜在収量性を示す気候登熟量示数は同じである。障害不稔発生に関係する穂ばらみ期冷害危険期の平均気温はわずかに低いかほぼ同じであるため,冷害発生の危険性は残る。一方,不稔発生をもたらす低温域の出現頻度には,地域間で差異がある。精米蛋白質含有率は同じであるが,アミロース含有率はやや低く,やや良食味である。米粒外観品質では被害粒歩合と着色粒歩合は一定の傾向がなく,未熟粒歩合はやや高い。精米白度は同じであるが,玄米白度はやや高い。以上の予測に対する技術的対応方向を示した。 相似文献
2.
Amyloid precursor protein (APP) is a type 1 transmembrane glycoprotein, and its homologs amyloid precursor-like protein 1 (APLP1) and amyloid precursor-like protein 2 (APLP2) are highly conserved in mammals. APP and APLP are known to be intimately involved in the pathogenesis and progression of Alzheimer’s disease and to play important roles in neuronal homeostasis and development and neural transmission. APP and APLP are also expressed in non-neuronal tissues and are overexpressed in cancer cells. Furthermore, research indicates they are involved in several cancers. In this review, we examine the biological characteristics of APP-related family members and their roles in cancer. 相似文献
3.
Pengfei Chen Honggang Chang Tao Peng Yongfan Tang Youquan Liu Chao Xiang 《应用聚合物科学杂志》2021,138(30):50314
Hydraulic fracturing with slickwater is a field-proven stimulation technology used in tight reservoirs. Because of the high pumping rate associated with slickwater fracturing, drag reduction (DR) is critical in minimizing pressure drop and the success of oilfield operations. In this paper, a new type of drag reducer (SPR) was synthesized with acrylamide and 12-allyloxydodecyl acid sodium, and its drag reduction performance was evaluated. The results showed that the new drag reducer features low molecular weight, fast-dissolving rate and low interfacial tension. The algorithm of estimating the drag reduction rate of non-Newtonian fluid SPR was proposed and validated. Empirical or semianalytical models for estimating the friction ratio (σ) or friction factor (λ or f) were used to simulate the turbulence behavior of the SPR drag reducer under different Reynolds numbers (Re). The modified Virk's correlation could accurately model the turbulent behavior of the SPR drag reducer. A unified calculation formula was established in this study for different pipe diameters. 相似文献
4.
《Ceramics International》2022,48(22):33115-33121
As a critical topological phase transition material, SrFeOx could play an essential role in the field of resistive memory. How to implement resistance-switching more softly and ensure the stability of materials has always been a relevant research hotspot. Regulating the oxygen environment during the deposition process of the films can effectively control the stoichiometry of the functional layer and then improve the resistance-switching characteristics of the device. In this paper, a SrFeOx hetero-film was prepared by oxygen pretreatment on the SrRuO3 surface before SrFeOx deposition, and the as-assembled micrometer-scale device exhibits a low set operating voltage of 0.6 V and favorable cycling characteristics. The SrFeOx hetero-film reveals a vertical brownmillerite superlattice-like structure with ~20 nm perovskite buffer layer, which benefits the connection and rupture of conductive filament. Additionally, XPS and UV–vis were used to analyze the bonding energy and band gap of SrFeOx hetero-film, and offers the experimental basis for the explanation of the conductive mechanism. Therefore, the device based on SrFeOx hetero-film with low operation voltage provides a reference for low power consumption research on topological phase transition material. 相似文献
5.
This paper presents results from a second stage of an experimental study of the dependence of steel fibers distribution along RFC prismatic specimens on the conventional reinforcement ratio and on the total amount of fibers in the concrete mix. The experimental program included two types of prismatic specimens with 30- and 60- kg/m3 of hooked-end steel fibers. Each specimen was sawed into equal segments and the numbers of fibers appearing at the cross-sections were counted and used for a further statistical analysis. This analysis comprised calculations of the average value and standard deviation of a non-dimensional variable, which represents the distribution of the total steel along the specimen. They were used to calibrate a theoretical model, which had been previously proposed by the authors. The test results showed reasonable to good agreement with the theoretical model. A comparison between the results of the 30- and 60-kg/m3 fibers shows that as the conventional reinforcement ratio increases, the standard deviations for the different mixtures approach each other. 相似文献
6.
K. Venkatadri S. Abdul Gaffar P. Rajarajeswari V. Ramachandra Prasad O. Anwar Bég B. Md. Hidayathulla Khan 《亚洲传热研究》2020,49(8):4281-4303
Modern magnetic nanomaterial processing operations are progressing rapidly and require increasingly sophisticated mathematical models for their optimization. Stimulated by such developments, in this paper, a theoretical and computational study of a steady magnetohydrodynamic nanofluid over an exponentially stretching/shrinking permeable sheet with melting (phase change) and radiative heat transfer is presented. Besides, wall transpiration, that is, suction and blowing (injection), is included. This study deploys Buongiorno's nanofluid model, which simulates the effects of the Brownian motion and thermophoresis. The transport equations and boundary conditions are normalized via similarity transformations and appropriate variables, and the similarity solutions are shown to depend on the transpiration parameter. The emerging dimensionless nonlinear coupled ordinary differential boundary value problem is solved numerically with the Newton-Fehlberg iteration technique. Validation with special cases from the literature is included. The increase in the magnetic field, that is, the Hartmann number, is observed to elevate nanoparticle concentration and temperature, whereas it dampens the velocity. Higher values of the melting parameter consistently decelerate the boundary layer flow and suppress temperature and nanoparticle concentration. A higher radiative parameter strongly increases temperature (and thermal boundary layer thickness) and weakly accelerates the flow. The increase in the Brownian motion reduces nanoparticle concentrations, whereas a greater thermophoretic body force strongly enhances them. The Nusselt number and Sherwood number are observed to be decreased with an increasing Hartmann number, whereas they are elevated with a stronger wall suction and melting parameter. 相似文献
7.
以‘秦美’猕猴桃果实为试材,于盛花期后28 d分别采用0(对照,清水)、5、10、20 mg/L 4个质量浓度的氯吡脲(1-(2-chloropyridin-4-yl)-3-phenylurea,CPPU)溶液进行蘸果处理,蘸果时间3~5 s,研究采前CPPU处理对‘秦美’猕猴桃贮藏期间果实硬度及细胞壁降解酶活力的影响。结果表明:CPPU处理加速了果实硬度、原果胶和纤维素质量分数的下降,提高了可溶性果胶质量分数及多聚半乳糖醛酸酶(polygalacturonase,PG)、果胶甲酯酶(pectin methylesterase,PME)、纤维素酶(cellulase,Cx)和β-半乳糖苷酶(β-D-galaetosidase,β-Gal)细胞壁降解活力。各处理组果实硬度与可溶性果胶质量分数和PG、Cx活力呈极显著负相关(P0.01),与原果胶、纤维素质量分数呈极显著正相关(P0.01);20 mg/L CPPU处理组果实的β-Gal活力与硬度呈显著负相关(P0.05)。CPPU处理提高了果实细胞壁降解酶的活力,促进了细胞壁的降解,加速了贮藏期间果实的软化,降低了果实的耐贮藏性。为维持猕猴桃采后果实硬度,延长贮藏期,生产中不宜使用CPPU处理,或使用的质量浓度不宜超过5 mg/L。 相似文献
8.
因煤层复杂渗流机理及低孔低渗特征,煤层气均需采取压裂改造措施进行开采。为了正确认识压裂参数对煤层气井产能、采出程度及井网部署的影响规律,从储层应力形变及煤层气解吸、扩散、渗流流固耦合分析出发,建立压裂井气水两相非线性渗流模型,研究裂缝参数、储层非均质性对井距及井网类型优化的影响,并且采用注入压降试井解释对压裂工艺参数进行评价。研究结果表明:煤层流体以非线性渗流为主,物性呈现先下降后上升的特征,存在启动压力梯度的影响;井距优化应考虑裂缝方向、裂缝穿透比、裂缝导流能力等因素的影响;矩形与菱形井网选择要参考储层各向异性系数的临界值;避免注入压降测试中井筒液面的变化及测试段的选择对试井解释结果的影响,提高压裂效果解释评价准确性。研究对煤层气压裂井裂缝、井网参数优化及提高压裂效果评价准确性具有较好的指导意义。 相似文献
9.
确定使用酶-3,5-二硝基水杨酸(3,5-dinitrosalicylic acid,DNS)法作为酵母胞内海藻糖定量测定方法,通过微波-浸提法对活性干酵母胞内海藻糖进行提取,采用单因素试验以酵母中海藻糖含量为参考指标优化该工艺中的微波功率、微波时间、三氯乙酸浓度、三氯乙酸体积、浸提温度、浸提时间,在此基础上对微波功率、微波时间、三氯乙酸浓度、三氯乙酸体积、浸提温度5个因素进行正交试验,优化后工艺条件为:针对1.5 g活性干酵母,微波功率231 W、微波时间40 s、三氯乙酸浓度0.7 mol/L、三氯乙酸体积40 m L、浸提温度55℃、浸提时间150 min。使用该工艺得到的活性干酵母中的海藻糖含量为280.15 mg/g,相对于优化前提高了15.2%。同时,利用该优化后工艺在现有面包酵母菌种中筛选出了一株高产海藻糖的菌株。在50 L自吸式发酵罐中将该菌株进行流加发酵,采用糖蜜进行溶氧反馈流加时最大酵母湿质量浓度为198.34 g/L,将流加工艺进行改进,提出称质量补料的流加方法将糖蜜、尿素、磷酸二氢铵作为流加营养源,实验发现发酵后最大酵母湿质量浓度可提高到264.82 g/L,相对于原工艺提高了33.52%,达到了面包酵母高密度培养的要求。发酵过程中将乙醇体积分数控制在0.7%~1.0%之间,将有效提高酵母湿质量浓度且保证其发酵力在650 m L/h以上,且工艺稳定性良好。 相似文献
10.
Responsible innovation (RI) offers a promising step towards a more responsible adoption of innovations, such as new and emerging technologies. However, how RI would be practised in different cultural contexts and settings is still less studied, especially in the context of developing countries. Taking the utilisation of CO2 in Indonesia as an empirical case, the purpose of this paper is to explore this issue through examining the influence of key characteristics of Indonesia's national culture on core dimensions of RI: anticipation, reflexivity, deliberation, responsiveness and participation. The different RI dimensions are applied in practice in a focus group discussion (FGD) and a round of interviews with different stakeholders that explored CO2 utilisation in the country. Hofstede's classification of national cultural dimensions is used to single out key focus points for attention in these RI processes in the Indonesian context. The results from the experiment illustrate that culture matters in the application of RI dimensions in practice. In the sense that in order for RI to work well, the governance of core RI processes such as participation and deliberation has to be adjusted to social norms of what is considered legitimate, desirable and good behaviour. These norms differ across societies. The findings further suggest ways of applying RI dimensions in practice. 相似文献