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1.
In this paper, we first re-examine the previous protocol of controlled quantum secure direct communication of Zhang et al.’s scheme, which was found insecure under two kinds of attacks, fake entangled particles attack and disentanglement attack. Then, by changing the party of the preparation of cluster states and using unitary operations, we present an improved protocol which can avoid these two kinds of attacks. Moreover, the protocol is proposed using the three-qubit partially entangled set of states. It is more efficient by only using three particles rather than four or even more to transmit one bit secret information. Given our using state is much easier to prepare for multiqubit states and our protocol needs less measurement resource, it makes this protocol more convenient from an applied point of view.  相似文献   
2.
A fluidized bed bioreactor (FBBR) was operated for more than 575 days to remove 2,4,6‐trichlorophenol (TCP) and phenol (Phe) from a synthetic toxic wastewater containing 80 mg L?1 of TCP and 20 mg L?1 of Phe under two regimes: Methanogenic (M) and Partially‐Aerated Methanogenic (PAM). The mesophilic, laboratory‐scale FBBR consisted of a glass column (3 L capacity) loaded with 1 L of 1 mm diameter granular activated carbon colonized by an anaerobic consortium. Sucrose (1 g COD L?1) was used as co‐substrate in the two conditions. The hydraulic residence time was kept constant at 1 day. Both conditions showed similar TCP and Phe removal (99.9 + %); nevertheless, in the Methanogenic regime, the accumulation of 4‐chlorophenol (4CP) up to 16 mg L?1 and phenol up to 4 mg L?1 was observed, whereas in PAM conditions 4CP and other intermediates were not detected. The specific methanogenic activity of biomass decreased from 1.01 ± 0.14 in M conditions to 0.19 ± 0.06 mmolCH4 h?1 gTKN?1 in PAM conditions whereas the specific oxygen uptake rate increased from 0.039 ± 0.008 in M conditions to 0.054 ± 0.012 mmolO2 h?1 gTKN?1, which suggested the co‐existence of both methanogenic archaea and aerobic bacteria in the undefined consortium. The advantage of the PAM condition over the M regime is that it provides for the thorough removal of less‐substituted chlorophenols produced by the reductive dehalogenation of TCP rather than the removal of the parent compound itself. Copyright © 2005 Society of Chemical Industry  相似文献   
3.
本文通过钢筋混凝土梁以及在受拉区部分地加入钢纤维的钢筋混凝土梁的试验及理论分析,研究了钢纤维混凝土层厚、钢纤维体积率和剪跨比对钢筋钢纤维增强部分混凝土梁受剪性能的影响,建立了与普遍钢筋混凝土梁受剪承载力计算公式相衔接的钢筋钢纤维增强部分混凝土梁受剪承载力的计算模型和计算公式.  相似文献   
4.
本文从 Wolf 的相干理论出发,把部分相干光束的交叉谱密度函数展开为空间完全相干模的叠加:进而讨论光阑对部分相干光束模式的影响。  相似文献   
5.
根据啮合型同向旋转双螺杆挤出非充满熔融的理论模型,对描述非充满熔融过程的主要物理量:固相高度变化函数、熔融速率及熔融区总长等进行了计算分析,并对有关影响因素进行了讨论。  相似文献   
6.
Several studies have been undertaken recently to adapt yttria partially stabilized zirconia (YPSZ) thermal barrier coating (TBC) characteristics during their manufacturing process. Thermal spraying implementing laser irradiation appears to be a possibility for modifying the coating morphology. This study aims to present the results of in situ (i.e., simultaneous treatment) and a posteriori (i.e., post-treatment) laser treatments implementing a high-power laser diode. In both cases, the coatings underwent atmospheric plasma spraying (APS). Laser irradiation was achieved using a 3 kW, average-power laser diode exhibiting an 848 nm wavelength. Experiments were performed to reach two goals. First, laser post-treatments aimed at building a map of the laser-processing parameter effects on the coating microstructure to estimate the laser-processing parameters, which seem to be suited to the change into in situ coating remelting. Second, in situ coating remelting aimed at quantifying the involved phenomena. In that case, the coating was treated layer by layer as it was manufactured. The input energy effect was studied by varying the scanning velocity (i.e., between 35 and 60 m/min), and consequently the irradiation time (i.e., between 1.8 and 3.1 ms, respectively). Experiments showed that coating thermal conductivity was lowered by more than 20% and that coating resistance to isothermal shocks was increased very significantly.  相似文献   
7.
田雨丰  李光强  肖永力  刘昱 《钢铁》2022,57(10):84-90
 在转炉炼钢过程中,石灰快速溶解对转炉高效脱磷具有十分重要的意义,石灰溶解过程中熔渣/石灰界面处形成的2CaO·SiO2产物层被认为是阻碍石灰溶解的关键因素。制备了具有两种不同CO2含量的部分煅烧石灰石,采用浸泡法研究了部分煅烧石灰石在转炉初渣中的溶解行为,并与纯石灰、石灰石的溶解行为进行比较。结果表明,石灰石溶解时在液态熔渣中CaO的传质系数为石灰的2.1倍,残留CO2质量分数为10%的部分煅烧石灰石的传质系数高达石灰石的6.7倍。在CO2质量分数为0~43.5%时,石灰的溶解速率先增大后减小。石灰溶解过程中形成的2CaO·SiO2层严重阻碍了FeOx的扩散,从而减缓了石灰的溶解。与石灰不同,石灰石分解产生的CO2能够破坏2CaO·SiO2层并破坏自身结构,有利于熔渣的渗透,这也适用于残留CO2的部分煅烧石灰石。制备纯石灰的过程中为了确保石灰芯部完全煅烧,因此极易导致石灰外表面发生过烧,而制备部分煅烧石灰石能在一定程度上解决表面过烧的问题。此外,与石灰石相比,部分煅烧石灰石由于表面是石灰外壳,溶解初期其表面附近的炉渣温降相对更低,能够避免溶解初期出现停滞阶段。在转炉富余热量有限的情况下,部分煅烧石灰石的石灰替换比高于石灰石,这取决于部分煅烧石灰石中的CO2残留量。  相似文献   
8.
为分析局部冲刷对部分埋入桩水平承载性状的影响,利用有限元软件ABAQUS模拟水平荷载作用下部分埋入单桩的受力。根据实际工况建立了部分埋入水平受荷桩的三维有限元计算模型,并将计算结果与现场试验结果进行对比,验证了所建模型的正确性。然后,通过算例分析了冲刷角度、深度、桩直径、桩顶约束条件和桩自由段长度对部分埋入桩水平承载性状的影响。分析结果表明:局部冲刷深度比冲刷角度对部分埋入桩的水平承载性状影响更大,局部冲刷对直径较大的桩体承载能力影响也更大,自由段长度的增大减小了桩体水平承载力,因此,在研究冲刷对桩基水平承载性状的影响时,应结合桩顶约束条件综合考虑。  相似文献   
9.
对钙镁磷肥(FMP)、过磷酸钙(SSP)和部分酸化磷肥(PAPR)在河南郑州西岗沙土和河南西华县潮土中的退化情况进行了研究。  相似文献   
10.
Glycol diesters and mixtures of mono- and diesters have been prepared from methyl esters of partially hydrogenated soybean oil fatty acids and diethylene, dipropylene, neopentyl and triethylene glycols. The catalyst used in these reactions was a mixture of calcium acetate/barium acetate (3∶1, w/w). The reactions were carried out under nitrogen with 0.5% catalyst at temperatures in the range of 190–275°C. Borated esters of mixed mono- and diesters were prepared with 0.33 equivalent of boric acid per 1.0 equivalent hydroxyl group on the ester. Refractive indices, viscosities, and flash and fire points were determined for diesters, mixed mono- and diesters, and mixed diesters and borated esters. The viscosities, flash points and fire points indicate that these esters can be used as a component of lubricating oils. Wear-prevention characteristics of mixed diesters and borated esters indicated that they can be used as antifriction additives in lubricating oils. Lecture presented at the joint meeting of the International Society for Fat Research and the American Oil Chemists' Society in Toronto, May 10, 1992.  相似文献   
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