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Cr(VI) can be released into soil as a result of mining, electroplating, and smelting operations. Due to the high toxicity of Cr(VI), its removal is necessary in order to protect ecosystems. Vermiculite is applied in situations where there is a high degree of metal pollution, as it is helpful during the remediation process due to its high cation exchange capacity. The Cr(VI) contained in the vermiculite should be extracted in order to recover it and to reduce the impact on the environment. In this work, adsorption equilibrium data for Cr(VI) in a simulated sorbent for soil remediation (a mixture that included both humic acid (HA) and vermiculite) were a good fit with the Langmuir isotherm model. The simulated sorbent for soil remediation was a favorable sorbent for Cr(VI) when it was in the test soil. An ionic liquid, [C4mim]Cl (1-butyl-3-methylimidazolium chloride), was studied to determine its efficiency in extracting Cr(VI) from the Cr- contaminated simulated sorbent in soil remediation. At 298 K and within 30 min, approximately 33.48 ± 0.79% of Cr(VI) in the simulated sorbent in soil remediation was extracted into [C4mim]Cl. Using FTIR spectroscopy, the absorbance intensities of the bands at 1032 and 1010 cm−1, which were attributed to C-O bond stretching in the polysaccharides of HA, were used to detect the changes in HA in the Cr-contaminated simulated sorbent for soil remediation before and after extraction. The results showed that Cr(VI) that has been absorbed on HA can be extracted into [C4mim]Cl. Using 1H NMR, it was observed that the 1-methylimizadole of [C4mim] Cl played an important role in the extraction of Cr(VI), which bonded with HA on vermiculite and was able to be transformed into the [C4mim]Cl phase. [ABSTRACT FROM AUTHOR]

Atomic layer plasma treatment (ALPT) enhances the corrosion protection of the ZrO 2 film prepared by thermal-driven ALD mode (TALD-ZrO 2) and further reduces the corrosion rate of Mg Ca alloy by more than an order of magnitude. The ALPT effect significantly increases the crystallinity and reduces the oxygen defects of TALD-ZrO 2 film. The ALPT time of 30 s has the most increase in the polarization resistance of TALD-ZrO 2 film, from 1.8kΩ·cm2 to 74.7kΩ·cm2. The enhancement of corrosion resistance of TALD-ZrO 2 film caused by the 30s-ALPT is equivalent to the thickness effect of increasing the thickness from 200 cycles to 300 cycles. ALPT technique is considered as a potential and feasible method to prepare TALD-ZrO 2 films with high film quality and excellent corrosion protection. • ALPT effectively enhances the corrosion protection performance of TALD-ZrO 2 film on Mg-Ca alloy. • Clarify that ALPT technique effectively improves the quality of the TALD-ZrO 2 films. • 30s-ALPT greatly enhances the polarization resistance from 1.8kΩ·cm2 to 74.7kΩ·cm2. • Clarify that ALPT significantly improves the long-term protection performance of TALD-ZrO 2 film on Mg-Ca alloy. [ABSTRACT FROM AUTHOR]

Abstract: Air-oxidation behavior of a Zr50Cu43Al7 bulk metallic glass (ZCA7-BMG) was studied over the temperature range of 400–500°C. The oxidation kinetics of the ZCA7-BMG generally followed a multiple-stage parabolic-rate law with its steady-state parabolic-rate constants (k p values) decreasing with increasing temperature, indicative of the occurrence of kinetics inversion. The scales formed on the ZCA7-BMG were strongly dependent on temperature, consisting mostly of tetragonal ZrO2 and CuO, and minor amounts of monoclinic ZrO2 and Cu2O at 400°C, while Cu2O was completely absent at T ⩾450°C. In addition, a minor amount of Al2O3 was further observed after the oxidation at 500°C, whose formation is responsible for the lowest oxidation rate, as compared to those at T ⩽450°C. [Copyright &y& Elsevier]

Process capability indices provide numerical measures on whether or not a process is able to produce products that meet prespecified quality targets and are often used by manufacturers to evaluate manufacturing performance. Although process yield is the primary focus of the performance criteria, a formula that combines the yield and the average process loss, called the quality yield index, has been developed. This index, the quality yield, can be viewed as the conventional process yield minus the truncated expected relative process loss within the specifications. Although cases with symmetric tolerances dominate in practical situations, cases with asymmetric tolerances can also occur. In this paper, we generalize the quality yield index for asymmetric tolerances. The generalization technique is justified, and some statistical properties of the estimated generalization are investigated. An application example on high-density light emitting diodes is also presented to illustrate the applicability of the generalization. [ABSTRACT FROM AUTHOR]

The loss-based process capability index Cpm, sometimes called the Taguchi index, has been proposed to the manufacturing industry to measure process performance. In this paper, we propose a method to assess the performance of a normally distributed process. We implement the theory of testing hypothesis using the natural estimator of Cpm, and provide an efficient program to calculate the p-values. We also provide tables of the critical values for some commonly used capability requirements. Based on the test, we develop a simple step-by-step procedure for in-plant applications. [ABSTRACT FROM AUTHOR]

Process capability indices Cp, Ca, Cpk and Cpm have been proposed to the manufacturing industry as capability measures based on various criteria including variation, departure, yield, and loss. It has been noted in recent quality research and capability analysis literature that both the Cpk and Cpm indices provide the same lower bounds on process yield, that is, Yield=2F(3Cpk)-1=2F(3Cpm)-1. In this paper, we investigate the behaviour of the actual process yield in terms of the number of nonconformities (in ppm) for processes with a fixed index value of Cpk=Cpm, but with different degrees of process centring, which can be expressed as a function of the capability index Ca. The results illustrate that it is advantageous to use the index Cpm over the index Cpk when measuring process capability, since Cpm provides better customer protection. [ABSTRACT FROM AUTHOR]

Process capability indices CPU and CPL have been widely used in the microelectronics manufacturing industry as capability measures for processes with one-sided specification limits. In this paper, the theory of statistical hypothesis testing is implemented for normal processes, using the uniformly minimum variance unbiased estimators of CPU and CPL. Efficient SAS computer programs are provided to calculate the critical values and the p-values required for making decisions. Useful critical values for some commonly used capability requirements are tabulated. Based on the test a simple but practical step-by-step procedure is developed for in-plant applications. An example on the voltage level translator manufacturing process is given to illustrate how the proposed procedure may be applied to test whether the process meets the preset capability requirement. [Copyright &y& Elsevier]

The effects of the plating current density ( j ) on the electroplated Cu microstructure, impurity distribution, and the solderability of the electroplated Cu were investigated. Analyses of electron backscatter diffraction and transmission electron microscopy showed that the Cu grain size ( D ) decreased from microscale to submicron-scale, and the predominant crystallographic orientation translated from [111]||ND + [101]||ND into [101]||ND (ND: Cu deposition direction) with increasing j . Time-of-flight secondary ion mass spectrometry analysis showed that the impurity content in the Cu platings (especially the Cl content) increased as a function of j . These investigations showed that j posed a significant influence on the characteristics of the electroplated Cu. Two intermetallic compound (IMC) species (η-Cu 6 Sn 5 and Cu 3 Sn) accompanied with some material defects (e.g., nanovoids and microcracks) formed at the solder/Cu pillar interface after reflow. The IMC (Cu 6 Sn 5 ) growth morphology and orientation, and the defect distribution were also strongly j -dependent. These j -dependent interfacial microstructures were closely related to different D and impurity contents of the Cu platings. The results of this study advanced our understanding of the effects of j on electrochemical metal deposition, and they were helpful in the development of the high-speed Cu electrodeposition technology. [ABSTRACT FROM AUTHOR]

Abstract: The oxidation behavior of a commercial Co69B12Si12Fe4Mo2Ni1 amorphous ribbon (Co6-AR) was studied over the temperature range of 400–600°C in dry air. The results showed that virtually no oxidation occurred at 400°C. On the other hand, the oxidation kinetics of the Co6-AR alloy at 450–600°C generally followed a multi-stage parabolic-rate law, and the parabolic-rate constants (k p values) tend to increase with increasing temperature. It was found that the oxidation rates of the glassy alloy are slower than those of pure Co, indicative of a better oxidation resistance. An exclusive scale of CoO was observed after the oxidation of the glassy alloy in the temperature range of interest, and several crystalline phases formed on the substrate beneath the scale, consisting of pure Co (both FCC and HCP structures), Co3B, Co2Si, CoFe, and Co2B (absent at 450°C), which indicated the occurrence of crystallization. [Copyright &y& Elsevier]

Abstract: The effect of Si addition on the oxidation of (Cu43Zr43Al7Ag7)99.5Si0.5 bulk metallic glass (CZ43S-BMG) was investigated over the temperature range of 375–500°C in dry air. The results generally showed that the oxidation rates of the CZ43S-BMG followed a multi-stage parabolic-rate law, and the oxidation rate constants (k p values) fluctuated with increasing temperature. It was found that the k p values of the CZ43S-BMG were slightly slower than those of the Si-free glassy alloy (Cu43Zr43Al7Ag7, named as CZ43-BMG). The scales formed on the CZ43S-BMG strongly depend on temperature, consisting of 3 different modifications of ZrO2 and CuO, and minor amounts of Cu2O (formed at T ≥425°C) and Al2O3 (only detected at 500°C). In addition, the glassy substrate remained amorphous nature at T ≤400°C, while it transferred to the crystalline phases of Cu10Zr7, ZrAl, and ZrSi2 after the oxidation at higher temperatures. [ABSTRACT FROM AUTHOR]

This paper aims to measure and simulate the warpages of 3D through-silicon via (TSV) die-stacked dynamic-random-access-memory (DRAM) packages during the manufacturing process. The related die stresses and keep-out zone (KOZ) for the stacked dies in the packages at room temperature are further calculated with the validated simulation model. The out-of-plane deformations (or warpages) of the packages from the full-field shadow moiré are documented under temperature loading and found consistent with those from finite-element method (FEM). The results of the stresses and KOZs at the proximity of a single TSV for each die in the package at room temperature are presented. It is found that the sizes of KOZs in four-die stacked DRAM packages with and without epoxy molding compound (EMC) at room temperature are dominated by the horizontal pMOS transistors and more than double the size in wafer-level die. The sizes of KOZs at each die are similar in this four-die stacked DRAM package, even though the stresses at each die are apparently different. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: This study aimed to further investigate the effects of agmatine on brain edema in the rats with middle cerebral artery occlusion (MCAO) injury using magnetic resonance imaging (MRI) monitoring and biochemical and histopathologic evaluation. Materials and methods: Following surgical induction of MCAO for 90min, agmatine was injected 5min after beginning of reperfusion and again once daily for the next 3 post-operative days. The events during ischemia and reperfusion were investigated by T2-weighted images (T2WI), serial diffusion-weighted images (DWI), calculated apparent diffusion coefficient (ADC) maps and contrast-enhanced T1-weighted images (CE-T1WI) during 3h–72h in a 1.5T Siemens MAGNETON Avanto Scanner. Lesion volumes were analyzed in a blinded and randomized manner. Triphenyltetrazolium chloride (TTC), Nissl, and Evans Blue stainings were performed at the corresponding sections. Results: Increased lesion volumes derived from T2WI, DWI, ADC, CE-T1WI, and TTC all were noted at 3h and peaked at 24h–48h after MCAO injury. TTC-derived infarct volumes were not significantly different from the T2WI, DWI-, and CE-T1WI-derived lesion volumes at the last imaging time (72h) point except for significantly smaller ADC lesions in the MCAO model (P<0.05). Volumetric calculation based on TTC-derived infarct also correlated significantly stronger to volumetric calculation based on last imaging time point derived on T2WI, DWI or CE-T1WI than ADC (P<0.05). At the last imaging time point, a significant increase in Evans Blue extravasation and a significant decrease in Nissl-positive cells numbers were noted in the vehicle-treated MCAO injured animals. The lesion volumes derived from T2WI, DWI, CE-T1WI, and Evans blue extravasation as well as the reduced numbers of Nissl-positive cells were all significantly attenuated in the agmatine-treated rats compared with the control ischemia rats (P<0.05). Conclusion: Our results suggest that agmatine has neuroprotective effects against brain edema on a reperfusion model after transient cerebral ischemia. [Copyright &y& Elsevier]

Abstract: We studied the magneotransport properties of granular films of FePt/C which were fabricated by using DC magnetron co-sputtering technique. Films were made at the sputtering pressures of 30 and 15mTorr, and with sputtering powers of 80 and 60W for each pressure. A large magnetoresistance of 6% at 2K was observed only for the film made at 80W and 15mTorr. Other magnetoresistance values were all below 1%. We also discussed the influence of carbon matrix on the giant magnetoresistance. [Copyright &y& Elsevier]

Advanced therapies have improved outcomes and also resulted in a growing risk of long‐term adverse health events. This study intends to estimate incidences of adverse health events and examine differences in adverse health events among childhood cancer survivors, and to understand the concerns of mothers after their child has completed cancer treatment. An explanatory sequential mixed‐method was used. A total of 201 paediatric cancer survivors' mothers with mean age 43.6 years were recruited. Of the survivors, 12.4% experienced five or more adverse health events. The incidence of adverse health events of altered body image, fatigue and neurocognitive problems were 31.54%, 14.77% and 12.53% respectively. Among survivors, significant differences in adverse health events of pain, endocrine problems and altered body image issues were identified. Survivors receiving radiotherapy, bone marrow transplants or completing treatment after 6–10 years experienced significantly more adverse health events. Maintaining health was the greatest concern for mothers, and the qualitative reports of their concerns could be categorised: living in uncertainty, and keeping forward‐looking. Childhood brain tumour survivors were identified as experiencing more adverse health events than other survivors. The need for healthcare teams to consider mothers' health concerns was highlighted. [ABSTRACT FROM AUTHOR]