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排序方式: 共有273条查询结果,搜索用时 15 毫秒
1.
Orthogonal signal correction (OSC) was a data preprocessing algorithm. It ensured that the filtered information was irrelevant to concentration data while using it to filter the noise from the original data. This paper extended the OSC application range from two-way data to three-way data. Two drug data sets, Enoxacin, Norfloxacin, Ciprofloxacin and Betamethasone, cortisone acetate, prednisone acetate, showed that the application of the OSC algorithm to three-way HPLC data was feasible and needed further research.  相似文献   
2.
Reactions between CH4 and CO2 under the action of continuous microwave discharge at atmospheric pressure were studied in a special homemade reactor,The main products were CO and H2,while acetylene and ethylene were also found in the products.Experimental results show that conversions of CH4 and CO2 could be higher than 90% without the presence of any catalyst,Effects of CO2/CH4 molar ratio and total flow rate of the feed gas on the reaction were also investigated.  相似文献   
3.
The equilibium constants of acid-base interaction between Mi(Octyl_dtp)_2 and alkylamine were determined by GLC method at several temperatures. Thermodynamic parameters △H and △S were evaluted as follows:ethylamine: △H=-11.5kJ mol~(-1) △S=-22.7J K~(-1) mol~(-1)diethylamine: △H=-18.1kJ mol~(-1) △S=-42.1J K~(-1) mol~(-1)The variations of logK versus temperature fit following equations:ethylamine: lgK=-1.19+598.9/Tdiethylamine: lgK=-2.20+945.6/T  相似文献   
4.

We propose a general framework for solving the group synchronization problem, where we focus on the setting of adversarial or uniform corruption and sufficiently small noise. Specifically, we apply a novel message passing procedure that uses cycle consistency information in order to estimate the corruption levels of group ratios and consequently solve the synchronization problem in our setting. We first explain why the group cycle consistency information is essential for effectively solving group synchronization problems. We then establish exact recovery and linear convergence guarantees for the proposed message passing procedure under a deterministic setting with adversarial corruption. These guarantees hold as long as the ratio of corrupted cycles per edge is bounded by a reasonable constant. We also establish the stability of the proposed procedure to sub-Gaussian noise. We further establish exact recovery with high probability under a common uniform corruption model.

  相似文献   
5.
Conventional oven drying (COD) and supercritical drying (SCD) methods were applied to the preparation of Mn-substituted hexaaluminate (BaMnA111O19-α) catalysts. The effect of drying methods on phase composition, specific surface area, pore structure, reduction behavior of Mn^3 ions, and combus-tion activity of the samples was investigated. The homogenous mixing of the components in the sol-gel process could be maintained by SCD, and the hexaaluminate phase was almost the only phase of the resulting materials after calcination. H2-TPR revealed that the Mn^3 ions in the sample obtained by SCD were easier to be reduced than that by COD. Moreover, the samples obtained by SCD have higher surface area, narrower pore size distribution, and higher combustion activity than those obtained by COD.  相似文献   
6.
Zeolite synthesis in contemporary chemical industries is predominantly conducted using organic structure-directing agents (OSDAs), which are chronically hazardous to humans and the environment. It is a growing trend to develop an eco-friendly and nuisanceless OSDA for zeolite synthesis. Herein, choline is employed as a non-toxic and green OSDA to synthesize high silica Y zeolite with SiO2/Al2O3 ratios of 6.5–6.8. The prepared Y zeolite samples exhibited outstanding (hydro)thermal stability at ultrahigh temperature owing to the higher SiO2/Al2O3 ratio. The XRF, SEM, 29Si-NMR and 13Na+ results suggested that choline plays a structure-directing role in the synthesis of Y zeolite, while the feed molar fraction of Na+ is a crucial determinant for the framework SiO2/Al2O3 ratio and the crystal morphology.  相似文献   
7.
Xylene isomer separation is considered one of the seven separation challenges that changed the world. In addition, the high-energy demand of xylene separation highlights the need for efficient novel adsorbents. Herein, the liquid-phase separation potential of the anion-pillared hybrid material SIFSIX-1-Cu was studied for preferential adsorption of o-xylene and m-xylene over p-xylene, which was inspired by a previous complexation crystallization method for separating m-xylene. We report detailed experimental liquid-phase adsorption experiments, yielding selectivities of 3.0 for o-xylene versus p-xylene and 2.6 for m-xylene versus p-xylene. Our theoretical calculations thus provide a reasonable explanation that the xylene adsorption selectivity is attributed to the C−H⋅⋅⋅F interaction, and the host–guest interaction order agrees with the adsorption priority: o-xylene > m-xylene > p-xylene.  相似文献   
8.
9.
Surgical procedures are susceptible to the cause of infections, which could induce delayed wound healing, oxidative stress and tissue ischemia. Multifunctional wound dressings (e.g., hydrogels) without the induction of antibiotics is promising for the elimination of surgical site infections and the associated complications. Herein, we report a reductionism approach for the fabrication of bioactive hydrogels to recapitulate antibacterial functions as well as antioxidant, pro-angiogenic and hemostatic properties in surgical infection treatments. The hydrogels composed of naturally derived Cirsium setosum extracts (CE, a traditional medicinal herb) and carboxymethyl chitosan (CS) show their capacity for surgical anti-infections on three different models (i.e., infectious random skin flap model, infectious skin defect model and infectious femur fracture model). Due to the innate bioactivities of CE and CS, CECS hydrogels can also reduce the bleeding loss (85% reduction) on a hemorrhaging liver model and improve the vascularization for skin flap regeneration. Overall, bioactive CECS hydrogels integrated with the ease and scalability of assembly process and biological activities without the addition of antibiotics is promising to act as multifunctional wound dressings for surgical anti-infections.  相似文献   
10.
以邻苯二胺、 2,5-二氨基苯磺酸和三氯化铝为原料, 通过无溶剂法大量制备了高效的红色荧光碳点 (R-CDs). 制得的碳点尺寸大约为2.4 nm, 含有13%的氮元素, 主要由高度石墨化的碳核及覆盖在其表面的大量官能团构成. 在不同的波长光激发下, 碳点在乙醇溶液中表现出不依赖于激发的红光发射, 其荧光峰位于 704 nm, 最大量子产率达到22%. 由于R-CDs具有优异的光学性质, 利用其构筑了紫外光激发的碳基白色发光二极管, 其色坐标为(0.33, 0.33), 非常接近自然光. 该研究为高效红色荧光碳点的大量制备提供了一种新路径, 同时拓宽了其在白光器件中的应用.  相似文献   
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