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混合梁斜拉桥钢混结合区4-d多尺度有限元分析

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清华大学学报（自然科学版） 2014年第10期54卷 1321-1326页

作者：周萌宁晓旭聂建国清华大学土木工程系土木工程安全与耐久教育部重点实验室北京100084

结合多尺度有限元建模与4-d有限元建模思路,提出混合梁斜拉桥钢混结合区4-d多尺度有限元建模方法,以重庆永川长江大桥为工程背景建立其钢混结合区4-d多尺度有限元模型,同时建立传统精细有限元模型作为对比。比较结果表明:4-d多尺度模型... 详细信息

结合多尺度有限元建模与4-d有限元建模思路,提出混合梁斜拉桥钢混结合区4-d多尺度有限元建模方法,以重庆永川长江大桥为工程背景建立其钢混结合区4-d多尺度有限元模型,同时建立传统精细有限元模型作为对比。比较结果表明:4-d多尺度模型不受失真区影响,结果更为准确;采用4-d多尺度有限元能够计算监测钢混结合区从施工建造至大桥服役全过程的实时力学响应及其变化,综合多个关键阶段的力学响应,获得更为安全可靠的设计依据。

关键词： 4-d 多尺度斜拉桥有限元分析 Saint-Venant区失真区

共存物质对O_3/H_2O_2工艺降解2,4-d的影响(Ⅱ)氯和过氧化氢动力学分析

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化工学报 2011年第10期62卷 2926-2931页

作者：陈岚权宇珩华北电力大学环境科学与工程学院河北保定071003

为了模拟实际水体中复杂的水质环境,在去离子水配制的溶液里加入少量无机盐、有机物,以及用自来水、地表水配制2,4-d溶液,采用O3/H2O2工艺处理水溶液中2,4-d污染物,通过跟踪反应液内氯离子和过氧化氢的浓度变化,考察共存物质对脱氯和过... 详细信息

为了模拟实际水体中复杂的水质环境,在去离子水配制的溶液里加入少量无机盐、有机物,以及用自来水、地表水配制2,4-d溶液,采用O3/H2O2工艺处理水溶液中2,4-d污染物,通过跟踪反应液内氯离子和过氧化氢的浓度变化,考察共存物质对脱氯和过氧化氢产生分解的影响。实验结果表明,脱氯量小于2,4-d去除量,2,4-d降解过程中的脱氯主要是由羟基自由基反应所导致的,抑制羟基自由基间接反应的共存物质能抑制脱氯过程;促进羟基自由基间接反应的共存物质能促进脱氯过程,2,4-d全部降解的同时,能达到接近全部脱氯。共存物质对过氧化氢分解速率常数影响较大,多数共存物质对过氧化氢分解速率常数具有促进作用;共存物质对过氧化氢产生速率常数影响较小,多数共存物质对过氧化氢产生速率常数具有抑制作用。

关键词：臭氧过氧化氢 2 4-d 共存物质脱氯

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检测2,4-d的一次性安培型免疫传感器

环境科学 2005年第6期26卷 169-172页

作者：蔡强余若祯何苗施汉昌清华大学环境科学与工程系环境模拟与污染控制国家重点联合实验室北京100084

2,4-d是广泛使用的除草剂,以2,4-d为检测目标,研究了安培型免疫传感器.首先采用1-乙基-3-(3-二甲基氨丙基)碳二亚胺盐酸盐(EdC)作为交联剂制备2,4-d与BSA以及PLL的偶联物.用结合比1:16的2,4-d与偶联物制备兔抗血清.免疫传感器的制备包括... 详细信息

2,4-d是广泛使用的除草剂,以2,4-d为检测目标,研究了安培型免疫传感器.首先采用1-乙基-3-(3-二甲基氨丙基)碳二亚胺盐酸盐(EdC)作为交联剂制备2,4-d与BSA以及PLL的偶联物.用结合比1:16的2,4-d与偶联物制备兔抗血清.免疫传感器的制备包括2个步骤,使用丝网印刷工艺制备一次性碳电极,然后通过戊二醛交联在电极表面固定2,4-d与多聚赖氨酸(PLL)的偶联物.待测水样与2,4-d抗血清和HRP酶标二抗进行间接免疫竞争反应.在HRP酶在邻苯二胺和H2O的共同作用下发生酶促反应,检测还原电流以反映2,4-d的浓度.试验了不同浓度抗血清和酶标二抗对检测信号的影响,结果表明,2,4-d的检测下限达到1.69ng/mL,线性区间1.69～30 000ng/mL,适合饮用水中2,4-d的检测要求.

关键词：丝网印刷电极 2 4-d 安培型免疫传感器

芥蓝游离小孢子胚胎发生途径及2,4-d对成胚的影响

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园艺学报 2021年第8期48卷 1605-1618页

作者：李智军曾晶谭铭喜谢景广东金作农业科技有限公司广州510640 广东省农业科学院作物研究所广州510640 韶关学院英东生物与农业学院广东韶关512005

采用改良dAPI荧光染色技术对芥蓝游离小孢子胚胎发生过程进行观察,同时比较培养基中添加2,4–二氯苯氧乙酸(2,4-d)对6个基因型芥蓝成胚的影响,并对再生植株的倍性和结实性进行鉴定。结果表明:芥蓝小孢子胚胎发生以B途径为主,但也存在A... 详细信息

采用改良dAPI荧光染色技术对芥蓝游离小孢子胚胎发生过程进行观察,同时比较培养基中添加2,4–二氯苯氧乙酸(2,4-d)对6个基因型芥蓝成胚的影响,并对再生植株的倍性和结实性进行鉴定。结果表明:芥蓝小孢子胚胎发生以B途径为主,但也存在A途径。小孢子第1次核非均等分裂或均等分裂形成不对称细胞即可建立极性特征,各类胚状体的形成似有其各自发育路径。2,4-d对成胚的影响因基因型而异,添加0.01~0.1 mg·L^(-1)2,4-d对‘绿宝’‘芊翠’和‘泽美’3个基因型芥蓝的成胚无显著影响;对于‘夏翠’,除0.1 mg·L^(-1)2,4-d显著降低子叶胚产量外,其他类型胚状体的产量不受影响;0.05和0.1 mg·L^(-1)2,4-d可分别显著增加‘顺宝’球形胚和鱼雷胚的产量,因而其总胚产量显著增加;对于成胚能力极强的‘顺宝2号’,心形胚、球形胚、其他类型胚状体及总胚产量均随着2,4-d浓度增大而显著提高,但子叶胚产量显著减少。添加2,4-d对‘顺宝2号’小孢子启动分裂无显著影响,但可维持或提高已启动分裂细胞的再分裂能力,减少中途退化或败育,从而提高胚产量。对获得150个再生株系进行倍性检测,单倍体株系占72.7%,dH系占22.7%,其他包括非整倍体和嵌合体在内的株系仅占4.6%。dH或单双倍体的嵌合体植株蕾期授粉后均能正常结实,而其他非整倍体(包括嵌合体)不结实或结实率极差。因此,可先根据植株花粉的有无、蕾期授粉后的结实性、叶形态以及生长势等判定出单倍体、dH和单倍体+二倍体植株,其他有花粉而不结实或结实不良的植株则可采用流式细胞仪检测其倍性。

关键词：芥蓝游离小孢子胚胎发生途径 2 4-d

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2,4-d调控番茄果形的转录基础

园艺学报 2023年第4期50卷 802-814页

作者：徐悦李子雄陈婕孙亮中国农业大学园艺学院蔬菜学系设施蔬菜生长发育调控北京市重点实验室北京100193

番茄冬春季设施生产中为提高坐果率而采用的2,4-d蘸花措施会导致畸形果率增加,其转录层面的机理尚不明确。本研究中对以醋栗番茄LA1589(Solanum pimpinellifolium accession LA1589)为背景的果形近等基因系WT、sun和ovate花蕾喷施2,4-d... 详细信息

番茄冬春季设施生产中为提高坐果率而采用的2,4-d蘸花措施会导致畸形果率增加,其转录层面的机理尚不明确。本研究中对以醋栗番茄LA1589(Solanum pimpinellifolium accession LA1589)为背景的果形近等基因系WT、sun和ovate花蕾喷施2,4-d,而后对花蕾转录组与成熟果实果形进行分析。结果发现,3个近等基因系在2,4-d处理3周后所形成的子房及其发育而来的成熟果实的果梗端均伸长,并最终导致子房与果实的形状指数增大,而在此过程中两个果形位点与2,4-d间存在互作。转录组分析发现,2,4-d处理可能通过激活生长素信号通路,促进生长素极性运输与细胞分裂素合成以及增加ATHB和bHLH转录因子的积累来改变果形;sun与ovate位点通过与2,4-d互作进一步增强了生长素积累、信号转导与极性运输,扩大了受影响的转录因子范围,最终强化了2,4-d对果形的影响;同时该互作还在sun与ovate近等基因系中分别上调了BRX与CKX5基因的表达来进一步增强上述过程;最后,ovate与2,4-d的互作导致两个SWEET基因的表达下调并可能影响糖类向子房中的运输。

关键词：番茄 2 4-d 生长素花蕾果形转录组 sun ovate

2,4-d在柑橘果实留树保鲜中的作用和可能机制研究

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园艺学报 2020年第11期47卷 2086-2094页

作者：祝建刘本勇李述举白芝兰刘聪邓晓东张豫谢宗周刘继红华中农业大学园艺林学学院园艺植物生物学教育部重点实验室武汉430070 湖北省兴山县特产局湖北兴山443711

以‘锦橙’(Citrus sinensis Osbeck)为材料,比较2,4-d不同浓度、不同施用时期对锦橙果实落果率和品质的影响,同时研究2,4-d在柑橘果实留树保鲜中的可能机制。结果发现,在盛花后200d(柑橘果实转黄期)施用20 mg·L^-1的2,4-d,能显著降低... 详细信息

以‘锦橙’(Citrus sinensis Osbeck)为材料,比较2,4-d不同浓度、不同施用时期对锦橙果实落果率和品质的影响,同时研究2,4-d在柑橘果实留树保鲜中的可能机制。结果发现,在盛花后200d(柑橘果实转黄期)施用20 mg·L^-1的2,4-d,能显著降低柑橘果实留树越冬的落果率,且对果实品质无不良影响,果实能够留树保鲜50 d左右。研究还发现,2,4-d处理能延缓果蒂离层的形成,抑制细胞壁降解相关酶基因CX16、PG2、PME1、PME2的表达。综上所述,2,4-d能够用于锦橙果实留树保鲜,其主要机制可能是抑制细胞壁降解和离层形成。

关键词：柑橘锦橙 2 4-d 果实留树保鲜离层细胞壁降解乙烯果实品质

Modeling the Interior of Black Holes Utilizing a 4-d Spatial Blackbody Radiation Model with an Exponential distribution

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Journal of High Energy Physics, Gravitation and Cosmology 2019年第3期5卷 953-983页

作者： Christopher Pilot Physics department Gonzaga University Spokane WA USA

This is a second follow up paper on a model, which treats the black hole as a 4-d spatial ball filled with blackbody radiation. For the interior radiative mass distribution, we employ a new type of truncated probability distribution function, the exponential distribution. We find that this distribution comes closest to reproducing a singularity at the center, and yet it is finite at 4-d radius, . This distribution will give a constant gravitational acceleration for a test particle throughout the black hole, irrespective of radius. The 4-d gravitational acceleration is given by the expression, , where R is the radius of the black hole, MR is its mass, and is the exponential shape parameter, which depends only on the mass, or radius, of the black hole. We calculate the gravitational force, and the entropy within the black hole interior, as well as on its surface, identified as the event horizon, which separates 3-d from 4-d space. Similar to a truncated Gaussian distribution, the gravitational force increases discontinuously, and dramatically, upon entry into the 4-d black hole from the 3-d side. It is also radius dependent within the 4-d black hole. Moreover, the total entropy is shown to be much less than the Bekenstein result, similar to the truncated Gaussian. For the gravitational force, we obtain, , where Mr is the radiative mass enclosed within a 4-d volume of radius r. This unusual force law indicates that the gravitational force acting upon a layer of blackbody photons at radius r is strictly proportional to the enclosed radiative energy, MrC2, contained within that radius, with 0.1λ being the constant of proportionality. For the entropy at radius, r, and on the surface, we obtain an expression which is order of magnitude comparable to the truncated Normal distribution. Tables are presented for three black holes, one having a mass equal to that of the sun. The other two have masses, which are ten times that of the sun, and 106 solar masses. The corresponding

关键词： Black Holes 4-d Spatial Blackbody Radiation Model Exponential distribution

In-Vitro Production of Anthocyanin in Sesbania grandiflora (Red Katuray) as Influenced by Varying Concentrations of 2,4-d and BA Added on MS Medium

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American Journal of Plant Sciences 2016年第15期7卷 2297-2306页

作者： donata A. Largado-Valler College of Agriculture Dr. Emilio B. Espinosa Sr. Memorial State College of Agriculture and Technology Mandaon Philippines

The study aimed to determine the anthocyanin content in callus cultures of Sesbania grandiflora L. (Red Katuray) using petal explants as influenced by 2,4-d and BA. The specific objective of this study is to determine the effect of plant growth regulators specifically auxin (2,4-d) and BA (Benzyladenine) on Murashige and Skoog’s (MS) medium in anthocyanin production. Earliest callus initiation was noted in 2.5 ppm to 5.0 ppm 2,4-d without BA and 2.5 ppm 2,4-d with 2.5 ppm BA. Same treatment combination had the highest degree of callus formation and obtained the greatest percentage of callus formation 2.5 ppm 2,4-d without BA and 2.5 ppm 2,4-d with 2.5 ppm BA. The heaviest weight of callus was registered at 2.5 ppm 2,4-d without BA. Significantly higher anthocyanin content was noted in 2.5 ppm to 5.0 ppm 2,4-d without or with 2.5 ppm BA, with 2.5 and 5.0 ppm BA and with 5.0 ppm 2,4-d and 2.5 ppm BA. There is a positive relationship between callus formation and anthocyanin production. Results showed that treatments that promoted significantly greater callus formation e.g. 2.5 ppm 2,4-d alone or in combination with 2.5 ppm BA also produced the highest anthocyanin content.

关键词： Anthocyanin In Vitro 2 4-d BA

On the Internal Structure of a Black Hole Utilizing a 4-d Spatial Blackbody Radiation Model

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Journal of High Energy Physics, Gravitation and Cosmology 2019年第3期5卷 719-772页

作者： Christopher Pilot Physics department Gonzaga University Spokane WA USA

A black hole is treated as a self-contained, steady state, spherically symmetric, 4-dimensional spatial ball filled with blackbody radiation, which is embedded in 3-d space. To model the interior distribution of radiation, we invoke two stellar-like equations, generalized to 4-d space, and a probability distribution function (pdf) for the actual radiative mass distribution within its interior. For our purposes, we choose a truncated Gaussian distribution, although other pdf’s with support, r ∈[0, R], are possible. The variable, r = r(4), refers to the 4-d radius within the black hole. To fix the coefficients, (μ,σ), associated with this distribution, we choose the mode to equal zero, which will give maximum energy density at the center of the black hole. This fixes the parameter, μ = 0. Our black hole does not have a singularity at the center, and, moreover, it is well-behaved within its volume. The rip or tear in the space-time continuum occurs at the event horizon, as shown in a previous work, because it is there that we transition from 3-d space to 4-d space. For the shape parameter, σ , we make use of the temperature just inside the event horizon, which is determined by the mass, or radius, of the black hole. The amount of radiative heat inflow depends on mass, or radius, and temperature, T2 ≥ 2.275K , where, T2, is the temperature just outside the event horizon. Among the interesting consequences of this model is that the entropy, S(4), can be calculated as an extrinsic, versus intrinsic, variable, albeit in 4-d space. It is found that S(4) is much less than the comparable Bekenstein result. It also scales not as, R2 , where R is the radius of the black hole. Rather, it is given by an expression involving the lower incomplete gamma function, γ(s,x), and interestingly, scales with a more complicated function of radius. Thus, within our framework, the black hole is a highly-ordered state, in sharp contrast to current consensus. Moreover, the model-dependent gravi

关键词： Black Hole 4-d Spatial Blackbody Radiation Model Internal Structure Radiative Pressure