质量控制图系统的实现及在SMT中的应用

本文将控制图理论与计算机技术相结合,开发了质量控制图系统.介绍了该系统的设计方案和关键技术问题,并以电子产品制造中监控SMT机的焊膏厚度为例说明了系统的应用.     

一种自适应多尺度积阈值的图像去噪算法

该文提出了平稳小波变换(Stationary Wavelet Transform, SWT )域自适应多尺度积阈值的图像去噪算法(SWT domain Multiscale Products, SWTMP)。与传统的阈值去噪算法不同,该阈值不是直接作用于小波系数,而是作用于小波系数的空间多尺度积。分析了SWT域含噪图像多尺度积的特点,提出了SWT域自适应多尺度积阈值的计算方法。多尺度积强化了图像的重要结构信息,弱化了噪声,在有效去噪的同时更多地保留了图像的边缘和细节。实验结果表明,所提算法对自然图像去噪后的视觉效果和性能指标均好于二进小波域多尺度积阈值(Adaptive Multiscale Products Thresholding, AMPT)去噪方法。     

Research on Equation of State For Detonation Products of Aluminized Explosive

The secondary reaction of the aluminum powder contained in an aluminized explosive is investigated, from which the energy loss resulted from the quantity reduce of the gaseous products is demonstrated. Moreover, taking the energy loss into account, the existing improved Jones-Wilkins-Lee (JWL) equation of state for detonation products of aluminized explosive is modified. Furthermore, the new modified JWL equation of state is implemented into the dynamic analysis software (DYNA)-2D hydro-code to simulate numerically the metal plate acceleration tests of the Hexogen (RDX)-based aluminized explosives. It is found that the numerical results are in good agreement with previous experimental data. In addition, it is also demonstrated that the reaction rate of explosive before the Chapman-Jouget (CJ) state has little influence on the motion of the metal plate, based on which a simple approach is proposed to simulate numerically the products expansion process after the CJ state.     

Mycotoxin contamination in corn smut (Ustilago maydis) galls in the field and in the commercial food products

Corn infected with Ustilago maydis, causal agent of common smut disease, produces galls that are used as food in certain cultures, but may be contaminated with mycotoxins. The objective of this study was to determine mycotoxin levels in common smut galls (CSGs) collected from the field at corn ear reproductive stages R1 through R5 and in commercial CSGs products. The study was conducted in 2012 and 2013. A simple extraction method for five mycotoxins was devised and the results showed the presence of these compounds in CSGs in corn during ear development at various physiological stages. Fumonisin was the major mycotoxin in CSG samples in both 2012 (63%, ≤150.7 μg g⁻¹) and 2013 (46.9%, ≤20.9 μg g⁻¹); followed by aflatoxin (2012: 2%, ≤14.7 ng g⁻¹; 2013: 30.6%, ≤10.8 ng g⁻¹) and zearalenone (2012: ≤41.70 ng g⁻¹; 2013: ≤12.40 ng g⁻¹). Deoxynivalenol (DON) was only detected in 2012 (≤1.6 μg g⁻¹), and cyclopiazonic acid was only detected in 2013 (≤3.18 μg g⁻¹). Commercial canned and fresh CSG samples also contained detectable amounts of mycotoxins including aflatoxin, fumonisin, CPA, and DON. Aspergillus flavus was isolated from selected 2013 CSG field samples at R2 or older (0–1.6 × 10⁶ cfu/g), whereas Fusarium spp were isolated at R1 or older (0–7.5 × 10⁷ cfu/g). These results indicate that CSGs can be infected with mycotoxigenic fungi and contaminated with mycotoxins. The incidence of mycotoxins in commercially available CSG products was highly variable and warrants further study.     

Multiplex ligation-dependent probe amplification (MLPA) for simultaneous detection of DNA from sunflower,poppy, flaxseed,sesame and soy allergenic ingredients in commercial food products

This work describes a multiplex ligation-dependent probe amplification (MLPA) technique for the simultaneous detection of five food allergens: sunflower, poppy, flaxseed, sesame and soy. Species-specific MLPA half-probes were designed to detect the DNA from the targeted species. Ligated probes were amplified by polymerase chain reaction (PCR) and amplicons were detected using capillary electrophoresis. The specificity of the MLPA system was assessed against DNA from more than 50 plant and animal species. The limit of detection (LOD) of the assay was determined to be 10 mg kg⁻¹in a model cookie experimentally spiked with different concentrations of the target species. The applicability of the MLPA was demonstrated through the analysis of 56 different commercial products (breads, pastries, cereals, chocolates, drinks, etc.), evidencing the presence of one or more undeclared allergenic ingredients in some of the tested samples. Real-time PCR assays were also performed to confirm and complement MLPA results. The MLPA technique has proved as a qualified screening tool for determining the presence of low amounts of sunflower, poppy, flaxseed, sesame and soy in processed foods.     

Innovative technologies to manage aflatoxins in foods and feeds and the profitability of application – A review

Aflatoxins are mainly produced by certain strains of Aspergillus flavus, which are found in diverse agricultural crops. In many lower-income countries, aflatoxins pose serious public health issues since the occurrence of these toxins can be considerably common and even extreme. Aflatoxins can negatively affect health of livestock and poultry due to contaminated feeds. Additionally, they significantly limit the development of international trade as a result of strict regulation in high-value markets. Due to their high stability, aflatoxins are not only a problem during cropping, but also during storage, transport, processing, and handling steps. Consequently, innovative evidence-based technologies are urgently required to minimize aflatoxin exposure. Thus far, biological control has been developed as the most innovative potential technology of controlling aflatoxin contamination in crops, which uses competitive exclusion of toxigenic strains by non-toxigenic ones. This technology is commercially applied in groundnuts maize, cottonseed, and pistachios during pre-harvest stages. Some other effective technologies such as irradiation, ozone fumigation, chemical and biological control agents, and improved packaging materials can also minimize post-harvest aflatoxins contamination in agricultural products. However, integrated adoption of these pre- and post-harvest technologies is still required for sustainable solutions to reduce aflatoxins contamination, which enhances food security, alleviates malnutrition, and strengthens economic sustainability.     

A survey on the Aflatoxin M1 occurrence and seasonal variation in buffalo and cow milk from Southern Italy

This study evaluates the aflatoxin M1 (AFM1) contamination in 804 samples of raw milk from cow and buffalo, collected randomly in Campania and Calabria regions of Southern Italy over a two years period.The competitive enzyme linked immunosorbent assay (ELISA) method was used to analyze AFM1 in the samples. AFM1 levels result above the CCβ value of 0.004 μg/kg in 51 (12.3%) cow milk samples and in 28 (7.2%) buffalo milk samples. Positive results from screening analysis were confirmed by high performance liquid chromatography with fluorimetric detection (HPLC-FLD) after a procedure of centrifugation, extraction and immunoaffinity column clean-up of milk. Only one cow milk sample exceeded the maximum limit (0.05 μg/kg) set by the European Regulation.The occurrence of AFM1 contamination was significantly (p < 0.05) higher in cold season, particularly fall, than in warm season, principally spring.Our results indicate that feedstuff used in the buffalo and cow farms were not highly contaminated with aflatoxins, determining a good quality of the analyzed milk. Therefore, the AFM1 contamination of the milk does not represent a serious public health problem in both regions in Southern Italy.     

ZV—1000公共广播系统及其应用

本文较全面介绍ZV-1000公共广播系统产品的特点、组成及功能,并列举在商场、宾馆等典型公共广播系统中的应用。最后指出:该系统作为替代进口产品,在国内公共广播系统工程中有着广泛的应用前景。     

Effect study of modulation of molecules of natural resin from black and Halepensis pinus in the removal of humidity from diesel fuel

One of the important stages in the preparation of fuel for the smooth progress of combustion is to remove humidity from it. Natural resin, a natural product from Pinus nigra and Pinus halepensis were used in order to remove water residues from petroleum fuels. The mass of resin (P. nigra and P. halepensis) was mixed with diesel fuel and the humidity eliminated, 38% and 69% of diesel fuel also. The proposed method can be used in a simple fuel cleaning process using a metal mesh vessel consisted of the natural resin of P. nigra sample.     

LaZSM5-Al-Mg催化剂上乙烯与甲苯烷基化制对甲基乙苯

以LaZSM5沸石为基质,添加铝和镁的氧化物所制得的择形催化剂,可大大提高乙烯与甲苯烷基化制甲基乙苯中对甲基乙苯选择性。考察了稀释气和反应产物的添加对烷基化反应的影响。失活后的催化剂可烧炭再生。