Using micro deep drawing with ironing stages to form stainless steel 304 micro cups

The needs of stainless steel 304 micro cups have been increasing tremendously due to the trend of miniaturization in medical and electronic devices, etc. For application purpose, it is highly desired to have stainless steel micro cups with high CH/OD (cup height/outer diameter) ratios. Due to the constraints of the limit draw ratio (LDR) of stainless steel 304 sheets in micro deep drawing, forming a micro cup with high CH/OD ratio at room temperature cannot be achieved by using a single stage deep drawing die. A process consisting of one micro deep drawing and two ironing stages was proposed for achieving this goal; three micro dies were designed, fabricated and used for experimental validation. A series of experiments were conducted by using the stainless steel 304 sheets of 200 μm thickness annealed at four different temperatures to understand the influence of size effects on this process for generating knowledge, know-how and technologies to form high quality stainless steel micro cups with large CH/OD ratio. No lubricant was used in this study. It was proven that the proposed process is a robust process as long as the sheets are annealed at the temperature no less than 900 °C for more than 3 min.     

Persistence of Human Noroviruses on Food Preparation Surfaces and Human Hands

The human noroviruses (NoV) are the major cause of acute non-bacterial gastroenteritis and are commonly transmitted by foodborne routes. Epidemiological evidence from propagated outbreaks, as well as environmental sampling, suggest that these viruses are environmentally stable. The purpose of this study was to examine the persistence of representative human NoV on the fingertips of volunteers and on commonly used food preparation surfaces. Human fingerpads and surfaces (stainless steel, Formica^®, and ceramic) were inoculated with 20% fecal suspensions of Norwalk virus (NV) or Snow Mountain virus (SMV). The virus inocula were recovered by elution at serial time points ranging from 0 to 120 min post-inoculation (for fingerpads) and after up to 42 days (for surfaces). The quantity of detectable viral RNA, expressed as genome equivalent particles (GEP) was evaluated using quantitative real-time RT-PCR (RT-qPCR). The amount of NV RNA on the surface decreased gradually over time, with an average reduction ranging from 1.5 to 2.9 log₁₀ GEP after 21–28 days storage under ambient conditions. SMV showed greater environmental persistence, with a 0.4–1.2 log₁₀ GEP reduction on all three surfaces after 42 days of ambient storage. On fingerpads, the amount of human NoV RNA declined slightly (<0.25 log₁₀) after 15 min and remained relatively unchanged thereafter (through 120 min). These results support the epidemiological evidence that food preparation surfaces and human hands can act as vehicles for human NoV transmission long after the initial contamination event has occurred.     

Enantioselective effects of herbicide imazapyr on Arabidopsis thaliana

The enantioselective toxicity of chiral herbicides in the environment is of increasing concern. To investigate the enantioselective effects of the chiral herbicide imazapyr on target organisms, we exposed Arabidopsis thaliana to imazapyr enantiomers and racemate. The results show that imazapyr was enantioselectively toxic to A. thaliana. The total chlorophyll content in A. thaliana was affected more by (+)-imazapyr than (±)-imazapyr and (?)-imazapyr. Concentrations of proline and malondialdehyde reflected a toxic effect in the order of (+)-imazapyr > (±)-imazapyr > (?)-imazapyr at every concentration. Acetolactate synthase (ALS) activity was inhibited more by (+)-imazapyr than (±)-imazapyr or (?)-imazapyr. At 100 mg L^?1 of imazapyr, ALS activity was 78%, 43%, and 19% with (?)-, (±)-, and (+)-imazapyr, respectively. The results suggest the significant enantioselective toxicity of imazapyr in A. thaliana for greater toxicity with (+)-imazapyr than (±)-imazapyr and (?)-imazapyr, which suggests that (+)-imazapyr has more herbicidal effect.     

Industrial Farming is Not Cruel to Animals

Critics of industrial animal agriculture (also known as “factory” farming) have argued that its practices are cruel, inhumane, or otherwise degrading to animals. These arguments sometimes form the basis of a larger case for the complete abolition of animal agriculture, while others argue for more modest welfare-based reforms that allow for certain types of industrial farming. This paper defends industrial farming against the charge of cruelty. As upsetting as certain practices may seem, I argue that they need not be construed as cruel or inhumane. Any link between industrial farming and cruelty or inhumanity is contingent on certain cultural, behavioral, and psychological facts that are person-dependent. For many people working in animal agriculture, these facts do not obtain. To be sure, industrial animal agriculture has real moral hazards that must be carefully avoided, but all that this shows is that working with animals is not for everyone.     

铁钙复合絮凝剂HC211用于钻井废水处理性能研究

探讨了在不同PH值、温度、剂量及酸化预处理条件下，铁钙复合絮凝剂HC211絮凝特性和絮凝效果的好坏。研究表明铁钙复合絮凝剂HC211在PH值为8－10，温度为15℃，剂量在4‰左右有好的絮凝效果。尤其在酸化预处理后，铁钙复合絮凝剂HC211絮凝效果更佳。     

Community‐based water supplies in Cikarang,Indonesia: are they sustainable?

Community‐based water supply (CBWS) is an example of how a community manages common pool resources (CPR). This results in an alternative approach to solve water supply problems in developing countries by enhancing community participation in managing water supply. This research evaluates the sustainability of five CBWS projects in Cikarang, Indonesia by using Ostrom's design principles, with additional sustainability factors found in the Sustainable Development Goal (SDG) on drinking water and groundwater sustainability. Quinn et al. (2007) criteria were used in the analysis, and the results show that the management of four CBWS institutions were absent and one CBWS institution was weak. With regards to the SDG's drinking water target, the CBWS institutions were unable to comply with safe water standards, and in terms of groundwater sustainability, efforts to monitor and sustain groundwater tables were absent. Results from this research suggest that more focus must be placed on water quality and groundwater sustainability for CBWS projects.     

Application of passive sampling on assessment of concentration distribution and health risk of volatile organic compounds at a high-tech science park

The objectives of this study are to investigate the volatile organic compound (VOC) distribution using passive samplers and to assess the resulting health risks in a high-tech science industrial park. With the advantages of passive sampling techniques, long-term and wide-area samples are collected. The results show TVOC concentrations in summer, fall, winter, and spring are 7.14?±?5.66 ppb, 18.17?±?5.81 ppb, 10.30?±?3.54 ppb, and 14.56?±?4.53 ppb, respectively; those on weekdays and weekends are 14.36?±?6.80 ppb and 9.87?±?4.86 ppb, respectively; and those in industrial and residential zones are 12.97?±?0.39 ppb and 11.13?±?0.68 ppb, respectively. Based on concentration variations, and benzene, toluene, ethylbenzene, and xylene ratios, we can resolve the source origins. Health risks are assessed based on the resulting concentrations. In the case of non-cancer chronic effects, long-term exposure to these concentrations does not support there is a risk of adverse health effects. However, potential cancer risks of exposure to these concentrations may occur, especially to carbon tetrachloride and benzene. By applying this study’s procedures, information on VOC concentration distribution, source identification, and health assessment can be obtained and they are applicable to similar studies.     

Study on safe air transporting velocity of nanograde aluminum,iron, and titanium

The process of delivering nanograde metal powders by a high-speed carrier gas is often subject to high explosion risks. This study adopted initial flow rates of 13.1, 8.5, 6.5, and 3.5 m/s for air transporting 30-nm titanium powder, 35-nm iron powder, and 35-nm aluminum powder to gauge the impact on a pipe bend in a 20-l-apparatus. The test results revealed that the 30-nm titanium powder caused an explosion at all initial flow rates; the 35-nm iron powder also caused an explosion, but dust explosion and sintering were eliminated when the flow rate was adjusted to less than 3.5 m/s; and the 35-nm aluminum powder exhibited no explosion or sintering at all flow rates. When pure nitrogen was used for transporting nanograde metal powders, no explosions occurred for all the three types of metal powders. The minimum ignition energy for these three types of nanograde metal powders was less than 1 mJ.     

Comparison of the Activity of Alcohol-Based Handrubs Against Human Noroviruses Using the Fingerpad Method and Quantitative Real-Time PCR

Noroviruses (NoV) are the most common cause of acute nonbacterial gastroenteritis in the United States, and human hands play an important role in their transmission. Little is known about the efficacy of hand hygiene agents against these highly infectious pathogens. We investigated the activity of seven commercially available hand hygiene products against human noroviruses by in vivo fingerpad tests. The in vivo activity of alcohol-based handrubs ranged from 0.10 to 3.74 log reduction and was not solely dependent on alcohol concentration. A handrub (VF481) based on 70% ethanol and a blend of other skin care ingredients reduced Norwalk virus (NV) by 3.74 log in 15 s and provided significantly greater NV reduction than all the other products tested (P < 0.001). Furthermore, VF481 was the most effective product tested against the NoV genogroup II strains Snow Mountain virus (GII.2) and a GII.4 strain. These results demonstrate that alcohol by itself is not effective against NoV, but effective formulation of alcohol-based handrubs can achieve significant reduction of norovirus RNA on fingers.     

An investigation on the potential of metal recovery from the municipal waste incinerator in Taiwan

This study aimed to identify distribution of metals and to estimate the amount of these metals that can be potentially recovered from incineration residues. First, the partitioning behavior of Cr, Cu, Fe, Cd, Al, Zn, and Pb in bottom ash and fly ash was investigated in one large municipal waste incinerator in Taiwan. In addition, the material flow analysis (MFA) method was used to estimate the material flux of metals within incinerator plant, and to calculate the amount of metal recovery. According to the findings of this study, six metals (Fe, Al, Cu, Zn, Cr, and Pb) concentrated in bottom ash mostly, while Cd existed primarily in fly ash. The weight percentages of Fe (4.49%), Al (5.24%), Cu (1.29%), Zn (2.21%), and Pb (0.58%) in incinerator ash are high, and even higher than the compositions of natural minerals. Finally, the amount of Cr, Cu, Fe, Cd, Al, Zn and Pb that can be potentially recovered from incineration residues will reach 2.69 x 10(2), 1.46 x 10(4), 4.91 x 10(4), 6.92 x 10(1), 5.10 x 10(4), 1.85 x 10(4) and 4.66 x 10(3) ton/yr, respectively.