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Background: This study aims to investigate the impact of test conditions on the results of the compression testing of microneedle arrays (MNAs). Methods: Uniaxial compression tests were conducted on polyglycolic acid-fabricated biodegradable MNAs. Load–displacement curves were obtained for varying conditions, including the number of microneedles (MNs) compressed simultaneously, compression speeds, and compression angles. Subsequently, the buckling load and stiffness were calculated, and the MN deformation during compression was observed. Results: The buckling load and stiffness per MN decreased significantly with a simultaneous increase in compressed MNs. The mean buckling load and stiffness of 52 MNs in single-needle compression tests were 0.211 ± 0.008 N and 13.9 ± 1.3 N/mm, respectively, with no variation among the three MNAs. However, a significant difference in buckling load and stiffness was observed among the MNs within the MNAs. Additionally, buckling loads and stiffnesses were significantly lower in certain MNs at the same location in different MNAs. Buckling load and stiffness decreased significantly during inclined compression compared to during vertical compression. While the tests evaluate the mechanical properties of MNAs, test results may vary depending on test conditions. Conclusions: Compression testing of the individual MNs comprising an MNA helps evaluate the mechanical properties of MNs and ensure the quality of MNAs. [ABSTRACT FROM AUTHOR]

Copyright of Food Research & Development is the property of Food Research & Development Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ground Improvement is the property of Journal of Ground Improvement Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: This study aims to investigate the impact of test conditions on the results of the compression testing of microneedle arrays (MNAs). Methods: Uniaxial compression tests were conducted on polyglycolic acid-fabricated biodegradable MNAs. Load–displacement curves were obtained for varying conditions, including the number of microneedles (MNs) compressed simultaneously, compression speeds, and compression angles. Subsequently, the buckling load and stiffness were calculated, and the MN deformation during compression was observed. Results: The buckling load and stiffness per MN decreased significantly with a simultaneous increase in compressed MNs. The mean buckling load and stiffness of 52 MNs in single-needle compression tests were 0.211 ± 0.008 N and 13.9 ± 1.3 N/mm, respectively, with no variation among the three MNAs. However, a significant difference in buckling load and stiffness was observed among the MNs within the MNAs. Additionally, buckling loads and stiffnesses were significantly lower in certain MNs at the same location in different MNAs. Buckling load and stiffness decreased significantly during inclined compression compared to during vertical compression. While the tests evaluate the mechanical properties of MNAs, test results may vary depending on test conditions. Conclusions: Compression testing of the individual MNs comprising an MNA helps evaluate the mechanical properties of MNs and ensure the quality of MNAs.

In this paper, by formulating a unified test scheme and integrating industry forces, the data collection of vibration condition for driving motor system of 21 different types of new energy passenger vehicles was completed based on the strengthened road surface in the test site. The above data are processed by selecting the maximum vibration energy value of each frequency segment and selecting envelope of vibration curve in each direction. Finally, a random vibration curve is formed for the tested components installed in the three positions of the new energy vehicle powertrain, body and drive motor. The final vibration curve were compared with the ISO 16750.3 CD draft. It is found that the general trend of vibration conditions constructed in this paper is consistent with the ISO draft. However, the vibration energy value is higher than ISO draft and higher than the measured vibration energy value of each enterprise. It is proved that the vibration condition formed by taking envelope of vibration curve is different from that of the actual driving motor. In this paper, further rectification measures are proposed to ensure the rationality of the subsequent construction of working conditions.

Copyright of Rolling Stock (1002-7602) is the property of Rolling Stock Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Plastics / Zhongguo Suliao is the property of Journal Office of CHINA PLASTICS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Xinyang Normal University Natural Science Edition is the property of Journal of Xinyang Normal University Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract In the current concept of repositories for radioactive waste disposal, compacted bentonite and bentonite-based materials with low hydraulic conductivity are being used as engineered barriers to inhibit the migration of radioactive nuclides. To ensure low hydraulic conductivity, the swelling characteristics of compacted bentonite are also important. However, previous studies have shown that swelling pressure measurements vary considerably and that this variation may be attributable to the differences in testing apparatuses. This variability increases the uncertainty in the design of the facilities. Thus, in this study, an improved stress–strain model for bentonite materials during the saturation process is proposed. The validity of the model is confirmed by comparing the experimental results obtained using several test methods with the simulated results from the model. Consequently, it is found that the swelling pressure test results of compacted bentonite, which are affected by several factors, such as the stiffness of the test cell, the height of the specimen, and the initial degree of saturation, can be numerically simulated using the proposed model. Thus, the effects of these factors on the test results can be evaluated quantitatively using the proposed model. [ABSTRACT FROM AUTHOR]

This study evaluated the flexural mechanical properties of various thermoplastic denture base polymers (six polyamides, four acrylic resins, polyester, polypropylene, and polycarbonate) by three different testing conditions; specimens were tested in water bath at 37®C (Wet/Water, by ISO 20795-1), or in ambient air (Wet/Air) after being immersed in distilled water for 50 h, or after desiccation for 7 days (Dry/Air). The mean ultimate flexural strength (UFS) and flexural modulus (FM) for most products ranged from 27 to 61 MPa and from 611 to 1,783 MPa respectively, which failed to meet the minimum requirements of the international standard, except for polycarbonate (89 and 2,245 MPa). The mean UFS and FM values were ranked Dry/Air>Wet/Air>Wet/Water (p<0.05). In conclusion, the flexural mechanical properties of denture base polymers varied with the products and were significantly affected by the testing medium (air or water) and specimen conditions (wet or dry). [ABSTRACT FROM AUTHOR]

Copyright of Journal of China University of Petroleum is the property of China University of Petroleum and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The friction behavior of core-shell nanostructure textured surfaces (CSNTSs) was systematically studied using indenters of various tip radii under several normal loads. The effects of the test parameters were investigated on two shell materials to elucidate friction mechanisms. The test parameters, material type, texture uniformity, and deformation had a significant impact on friction values. At the lowest load, adhesion led to the highest coefficient of friction (COF) on both surfaces for all tip sizes tested. At low contact pressures, the Al/diamond-like carbon (DLC) CSNTS experienced a lower COF than the Al/amorphous silicon (a-Si) CSNTS due to DLC has better tribological property than a-Si. At higher contact pressures, more severe deformation and thus higher COF occurred on the Al/DLC CSNTS. [ABSTRACT FROM AUTHOR]

Abstract: With a rapid increase in size and complexity of software today, the scope of software testing is also expanding. The efficiency of software testing needs to be improved in order to ensure the appropriate delivery deadline and cost of software development. For improving efficiency of software testing, the test needs to be designed in a way that the number of test cases is sufficient and appropriate in quantity. Test analysis is the activity to refine Application Under Test (AUT) into proper size that test design techniques can be applied to. It is for designing the test properly. However, the classification for proper size depends on individual's own judgments. This paper proposes a test analysis method for the black box testing using a test category that is the classification based on fault and AUT knowledge. [Copyright &y& Elsevier]

Molluscan species can be affected by various anthropogenic substances. Yet, these effects are disregarded in chemical risk assessment as molluscs are unrepresented in standard OECD guidelines. The project “validation of a mollusc reproduction test” (Federal Environment Agency, code 371165417) deals with the development of a test method with the mudsnailPotamopyrgus antipodarumfor OECD purposes. In this context, the influence on reproduction of both, different media and varying snail density, has been observed in independent experiments. Further, the impact of density on the outcome of subsequent cadmium (Cd) toxicity in a test has been investigated to refine the existing methodology. First, adult snails were kept in different test media for 12 weeks. Second, snail density was increased for 4 weeks to induce stress. Snails from each density scenario were used for another 4 weeks in a reproduction test at an equal density with 12 μg Cd/L, respectively. Significant differences in reproduction between medium groups were noted after 4 and 8, but not 12, weeks. Further, reproduction was significantly altered by snail density in the beakers but after subsequent 4 weeks at a constant density, no differences were observed between control groups. Cd reduced reproduction and this effect increased with snail density in the pre-exposure period, demonstrating that a previous stress factor may result in increased sensitivity to chemicals and underlines the need for more standardized breeding conditions to minimize effect variations. Based on the outcome of this study, an acclimatization period of 12 weeks must be guaranteed for specimens transferred to another medium. Further, 4 weeks of acclimatization are necessary after density stress. An additional 12 weeks density experiment showed that medium volume in each replicate can be decreased by half to save on chemicals, water and space during tests. [ABSTRACT FROM PUBLISHER]

Abstract: The mutagenicity levels of tap water in Japan were surveyed using the Ames test. Tap water samples (179) were collected at 17 sampling sites located from the northern tip (Hokkaido) to the southern tip (Kagoshima Prefecture). The mutagenicity values ranged from under the detection limit to 3600net rev.L−1. The average mutagenicity was 1100net rev.L−1 and the levels were significantly higher in the wintertime than in the summertime. The average mutagenicity of each site ranged from under the detection limit to 2000net rev.L−1. There was no significant correlation of the mutagenicity with TOC, A 260 or THMs. The highest positive ratios of the Ames test and the umu test were 92% under the condition TA100−S9 and 9% under the condition NM2009−S9, respectively, which indicated that the Ames test has higher sensitivity for the test of tap water than the umu test. This survey incorporated the 1992–1993 survey. The comparison of these survey-results in a further study will reveal the improvement of Japanese tap water quality from the perspective of mutagenicity. [Copyright &y& Elsevier]

Cold-stress tests are used for evaluating vascular disorders in the hand-arm vibration syndrome, and the value of such tests based on finger skin temperature measurement has been investigated. However, there is a wide difference in the test conditions among countries and researchers. Standardization of the cold-stress tests is currently under discussion within the International Organization for Standardization. We reviewed various aspects of the cold-stress tests involving finger skin temperature measurement, including water temperature, hand immersion time and other test conditions, and evaluated their diagnostic significance. Water temperature varied from 0 °C to 15 °C and hand immersion time varied from 0.5 min to 20 min. The cold-stress tests are associated with relatively severe suffering, thus, higher temperature of cold water and shorter time of immersion are desirable. To date, however, there has not been sufficient data indicating diagnostic value in a test method involving cold water at around 15 °C. Diagnostic value is also influenced by other test conditions, such as room temperature, season, use of ischemia during immersion. For standardization of the cold-stress test involving finger skin temperature measurement, these factors must be considered together with water temperature and immersion time. [ABSTRACT FROM AUTHOR]

In order to explore the various factors effect on the mohair felting properties, the felting property of mohair with different lengths was examined by using felting ball test method, and comparison with the cashmere fiber, the test result showed that with the increase of the temperature and the time, the volume decreased and the density increased gradually. At the same experimental conditions, with the shorter of the fiber length , the felting performance was weaker, the volume was greater and the density was smaller. When the length of the mohair becomes the quarter of the original length, the felting performance turned weaker, and showed loose state. [ABSTRACT FROM AUTHOR]

Because of the scales on the cashmere fiber surface, the using process will lead to the phenomenon of fabric shrinkage, shape instability and reduce the wearability. In order to test the performance of the regular felting, in this paper, shrink-ball method was used to test white cashmere fiber, purple cashmere fiber, shrink cashmere fiber, dyed cashmere fiber' s felting degree. The experiment showed that the volume of the fiber felting body was gradually smaller with the increase of the temperature and time, when the soap temperature exceeded 30 °C , time longer than 30 mm, white cashmere had a serious felting. Shrink-proof treatment of the white cashmere significantly reduced the degree of felting, cashmere fiber's staining had no effect on the extent of its shrinkage. [ABSTRACT FROM AUTHOR]

Failure mechanism of hermetically sealed fiber optical communication devices under damp-heat aging (85°C and 85% relative humidity) is discussed linked to degradation of physical properties of the cured epoxy, i.e., glass transition temperature, coefficient of thermal expansion, and adhesion. Recovery of output power or insertion loss from the degraded devices is reported after baking at a certain temperature. This reversible phenomenon is attributed to moisture absorption under the test condition and desorption at high temperature bake. This letter demonstrates that a correlation exists between the performance of optical communication devices and physical properties of the cured epoxy used for the subassembly. [ABSTRACT FROM PUBLISHER]

This study evaluated the flexural mechanical properties of various thermoplastic denture base polymers (six polyamides, four acrylic resins, polyester, polypropylene, and polycarbonate) by three different testing conditions; specimens were tested in water bath at 37°C (Wet/Water, by ISO 20795-1), or in ambient air (Wet/Air) after being immersed in distilled water for 50 h, or after desiccation for 7 days (Dry/Air). The mean ultimate flexural strength (UFS) and flexural modulus (FM) for most products ranged from 27 to 61 MPa and from 611 to 1,783 MPa respectively, which failed to meet the minimum requirements of the international standard, except for polycarbonate (89 and 2,245 MPa). The mean UFS and FM values were ranked Dry/Air>Wet/Air>Wet/Water (p<0.05). In conclusion, the flexural mechanical properties of denture base polymers varied with the products and were significantly affected by the testing medium (air or water) and specimen conditions (wet or dry).