LM339在数控电路中的应用

本文介绍了LM339在数控电路中的应用，并对其电路进行了分析。     

Enhancing self-scheduling algorithms via synchronization and weighting

Existing dynamic self-scheduling algorithms, used to schedule independent tasks on heterogeneous clusters, cannot handle tasks with dependencies because they lack the support for internode communication. To compensate for this deficiency we introduce a synchronization mechanism that provides inter-processor communication, thus, enabling self-scheduling algorithms to handle efficiently nested loops with dependencies. We also present a weighting mechanism that significantly improves the performance of dynamic self-scheduling algorithms. These algorithms divide the total number of tasks into chunks and assign them to processors. The weighting mechanism adapts the chunk sizes to the computing power and current run-queue state of the processors. The synchronization and weighting mechanisms are orthogonal, in the sense that they can simultaneously be applied to loops with dependencies. Thus, they broaden the application spectrum of dynamic self-scheduling algorithms and improve their performance. Extensive testing confirms the efficiency of the synchronization and weighting mechanisms and the significant improvement of the synchronized–weighted versions of the algorithms over the synchronized-only versions.     

Synthesis of nanozirconooligocarbosilanes

We describe the first chlorine-free synthesis of nanozirconooligocarbosilanes through thermal cocondensation of low-molecular oligocarbosilanes and zirconium tetrakis(diethylamide). The starting reagents, reaction intermediates, and final products have been characterized by ¹H, ¹³C, and ²⁹Si nuclear magnetic resonance, UV and IR spectroscopy, gel-permeation chromatography, thermogravimetry, transmission electron microscopy (TEM), and elemental analysis. The synthesized nanozirconooligocarbosilanes have been used to fabricate ceramic fibers and matrices through thermal and chemical processing. TEM results demonstrate that the particles of zirconium and products of its reactions with silicon, carbon, and nitrogen range in size from 10 to 20 nm in the oligomers and from 20 to 30 nm in the ceramics.     

具有在线修正功能的镍氢电池SOC估算方法

介绍了电动汽车用镍氢电池荷电状态(SOC)的常用估算方法。针对安时积分法结合开路电压法估算蓄电池SOC时累积误差偏大的问题，测试了镍氢电池充放电特性曲线，并对曲线进行多项式拟合，提出了根据电池不同工况进行条件判断，对估算值进行在线修正的估算方法。实践证明，本文所述估算方法能明显地减小累积误差，更好地满足电池SOC的估算要求。     

Betulinic Acid in Complex with a Gamma-Cyclodextrin Derivative Decreases Proliferation and in Vivo Tumor Development of Non-Metastatic and Metastatic B164A5 Cells

Betulinic acid, a very promising anti-melanoma agent, has very low water solubility that causes low bioavailability. To overcome this inconvenience, a highly water-soluble cyclodextrin was used (octakis-[6-deoxy-6-(2-sulfanyl ethanesulfonic acid)]-γ-cyclodextrin). The complex was physico-chemically analyzed using differential scanning calorimetry (DSC), X-ray and scanning electron microscopy (SEM) methods and then in vitro tested for its antiproliferative activity by the MTT assay and by cell cycle analysis. Finally, the complex was tested in vivo using an animal model of murine melanoma developed in C57BL/6J mice, where it caused a reduction in tumor volume and weight. The study revealed the beneficial influence of betulinic acid inclusion into the cyclodextrin in terms of antiproliferative activity and in vivo tumor development.     

Synthesis of single-wall carbon nanotubes by excimer laser ablation

We report the KrF excimer laser ablation of carbonaceous targets in an innovative laser ablation chamber. The targets have been prepared using a new approach, without pressing or hot pressing of the composition. The Co/Ni doped target has yielded single-wall carbon nanotubes with a narrow diameter distribution. High-resolution transmission electron microscopy has been used along with the confocal Raman microscopy to characterize the products obtained. Thermogravimetric analysis confirms the presence of multiple carbonaceous species with different oxidation temperatures.     

Pulse laser ablation system for carbon nano-onions fabrication

A new laser ablation chamber design for KrF excimer laser synthesis of carbon nanomaterials, including nano-onions, is reported. The conditions for carbon nano-onions deposition, using excimer laser to ablate a commercial pure graphite target, were investigated. The transmission electron microscopy analysis of the collected deposits indicates that mainly nano-onions are obtained when pure graphite targets are ablated. Raman spectroscopy identified without doubt production of carbon nano-onions.     

Cell therapy using an array of ultrathin hollow microneedles

Microsystem Technologies - Cell transplantation traditionally employs needles to inject donor cells into tissues to treat certain diseases. However, it is difficult for the current method to...     

FT-NIR spectroscopy for the quality characterization of apricots (Prunus armeniaca L.)

Abstract: The nondestructive assessment of apricot fruit quality (Bora cultivar) was carried out by means of FT-NIR reflectance spectroscopy in the wavenumber range 12000 to 4000 cm⁻¹. Samples were harvested at four different ripening stages and scanned by a fiber optical probe immediately after harvesting and after a storage of 3 d (2 d at 4 °C and 1 d at 18 °C); the flesh firmness (FF), the soluble solids content (SSC), the acidity (A), and the titratable acidity (malic and citric acids) were then measured by destructive methods. Soft independent modeling of class analogy (SIMCA) analysis was used to classify spectra according to the ripening stage and the storage: partial least squares regression (PLS) models to predict FF, SSC, A, and the titratable acidity were also set-up for both just harvested and stored apricots. Spectral pretreatments and wavenumber selections were conducted on the basis of explorative principal component analysis (PCA). Apricot spectra were correctly classified in the right class with a mean classification rate of 87% (range: 80% to 100%). Test set validations of PLS models showed R² values up to 0.620, 0.863, 0.842, and 0.369 for FF, SSC, A, and the titratable acidity, respectively. The best models were obtained for the SSC and A and are suitable for rough screening; a lower power prediction emerged for the other maturity indices and the relative predictive models are not recommended. Practical Application : The results of the study could be used as a tool for the assessment of the ripening stage during the harvest and the quality during the postharvest storage of apricot fruits.