bluuebunny/crossref_metadata_2025 huggingface dataset:
Clinically assisted hydration in patients in the last days of life (‘CHELsea II’ trial): a cluster randomised trial
Authors: Davies Andrew , Waghorn Melanie , Roberts Megan , Gage Heather , Skene Simon S
Published: November 2022

Introduction

Provision of clinically assisted hydration (CAH) at the end of life is one of the most contentious issues in medicine. The aim of the ‘CHELsea II’ trial is to evaluate CAH in patients in the last days of life. The objectives are to assess the effect of CAH on delirium, audible upper airway secretions, pain and other symptoms, and overall survival, as well as the tolerability of CAH, and the health economic impact.

Methods and analysis

The study is a cluster randomised trial, involving 80 sites/clusters (mainly hospices) and 1600 patients. Sites will be randomised to an intervention, and this will become the standard of care during the trial. Intervention ‘A’ involves continuance of drinking (if appropriate), mouth care and usual end-of-life care. Intervention ‘B’ involves continuance of drinking, mouth care, usual end-of-life care and CAH, that is, parenteral fluids. The fluid may be given intravenously or subcutaneously, the type will be dextrose saline (4% dextrose, 0.18% sodium chloride) and the volume will be dependent on weight.

Participants will be assessed every 4 hours by the clinical team. The primary endpoint is the proportion of participants who develop delirium determined using the Nursing Delirium Screening Scale (using a cut-off score of ≥2). A mixed-effects logistic regression will be used to assess the difference in the odds of developing delirium between the interventions.

Ethics and dissemination

Ethical committee approval has been granted by the Brighton and Sussex Research Ethics Committee (REC) (main REC for the UK: reference—IRAS 313640), and by the Scotland A REC (REC for adults with incapacity in Scotland: reference—22/SS/0053-IRAS-317637). The consent process follows the Mental Capacity Act: if the patient has capacity, then consent will be sought in the normal way; if the patient does not have capacity, then a personal/nominated consultee will be approached for advice about the patient entering the study. The consent process is slightly different in Scotland.

The results of the trial will be published in general medical/palliative care journals, and presented at general medical/palliative care conferences.

Trial registration number

ISRCTN65858561.
Characterisation of the safety profile of evobrutinib in over 1000 patients from phase II clinical trials in multiple sclerosis, rheumatoid arthritis and systemic lupus erythematosus: an integrated safety analysis
Authors: Montalban Xavier , Wallace Daniel , Genovese Mark C , Tomic Davorka , Parsons-Rich Dana , Le Bolay Claire , Kao Amy H , Guehring Hans
Published: November 2022

Objective

Analyse the integrated safety profile of evobrutinib, a Bruton’s tyrosine kinase inhibitor (BTKi), using pooled data from multiple sclerosis (MS), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) trials.

Methods

Phase II, randomised, double-blind, placebo-controlled trial data were analysed (N=1083; MS: n=213, 48 weeks (W); RA: n=390, 12W; SLE: n=480, 52W). The analysis included all patients who received ≥1 dose of evobrutinib (25 mg or 75 mg once daily, or 50 mg or 75 mgtwice daily) or placebo. Descriptive statistics and exposure-adjusted incidence rates (EAIR) were used to report treatment-emergent adverse events (TEAEs).

Results

Data from 1083 patients were pooled: evobrutinib, n=861; placebo, n=271 (sum >1083 due to MS trial design: n=49 received both placebo (W0–24) and evobrutinib 25 mg (W25–48)); median follow-up time (pt-years): evobrutinib, 0.501; placebo, 0.463. Across indications, the proportion of patients with TEAEs and the EAIR were similar for evobrutinib and placebo (66.2% (247.6 events/100 pt-years) vs 62.4% (261.4 events/100 pt-years)). By indication, the EAIR (events/100 pt-years) of TEAEs for evobrutinib versus placebo were: MS: 119.7 vs 148.3; RA: 331.8 vs 306.8; SLE: 343.0 vs 302.1. Two fatal events occurred (in SLE). The serious infections EAIR was 2.7 and 2.1 events/100 pt-years for evobrutinib and placebo. For previously reported BTKi-class effects, the EAIR of transient elevated alanine aminotransferase/aspartate aminotransferase TEAEs (events/100 pt-years) with evobrutinib versus placebo was 4.8 vs 2.8/3.5 vs 0.7, respectively. IgG levels were similar in evobrutinib/placebo-treated patients.

Conclusions

This is the first BTKi-integrated safety analysis that includes patients with MS. Overall, evobrutinib treatment (all doses) was generally well tolerated across indications.

Trial registration numbers

NCT02975349,NCT03233230,NCT02975336.
The role of hyperbaric oxygen therapy in the management of perioperative peripheral nerve injury: a scoping review of the literature
Authors: Brenna Connor TA , Khan Shawn , Katznelson Rita , Brull Richard
Published: November 2022

Background/importance

Peripheral nerve injury is an uncommon but potentially catastrophic complication of anesthesia and surgery, for which there are limited effective treatment options. Hyperbaric oxygen therapy is a unique medical intervention which improves tissue oxygen delivery and reduces ischemia via exposure to oxygen at supra-atmospheric partial pressures. While the application of hyperbaric oxygen therapy has been evidenced for other medical conditions involving relative tissue ischemia, its role in the management of peripheral nerve injury remains unclear.

Objective

This scoping review seeks to characterize rehabilitative outcomes when hyperbaric oxygen therapy is applied as an adjunct therapy in the treatment of perioperative peripheral nerve injury.

Evidence review

The review was conducted according to Preferred Reporting Items for Systematic Reviews and Meta‐Analyses guidelines for scoping reviews, using a systematic screening and extraction process. The search included articles published from database inception until June 11, 2022, which reported clinical outcomes (in both human and non-human models) of peripheral nerve injury treated with hyperbaric oxygen therapy.

Findings

A total of 51 studies were included in the narrative synthesis. These consisted of animal (40) and human studies (11) treating peripheral nerve injury due to various physiological insults. Hyperbaric oxygen therapy protocols were highly heterogenous and applied at both early and late intervals relative to the time of peripheral nerve injury. Overall, hyperbaric oxygen therapy was reported as beneficial in 88% (45/51) of included studies (82% of human studies and 90% of animal studies), improving nerve regeneration and/or time to recovery with no reported major adverse events.

Conclusions

Existing data suggest that hyperbaric oxygen therapy is a promising intervention in the management of perioperative peripheral nerve injury, in which tissue ischemia is the most common underlying mechanism of injury, neurological deficits are severe, and treatment options are sparse. This positive signal should be further investigated in prospective randomized clinical trials.
Hydro-mechanical coupling effect on water permeability of intensely weathered sandstone
Authors: Cai Guoqing , Liu Qianqian , Yang Yu , Zhou Annan , Li Xu
Published: November 2022

The combined effect of stress and seepage is an important reason of engineering geological problems such as landslides, dam failures, and tunnel collapse. However, due to the limitations of the test apparatus, the existing studies rarely consider the stress effect in the seepage process. In this study, a soil column apparatus based on the wetting front advancing method was developed to explore the permeability properties of intensely weathered sandstone in a wide range of suction (10∼106 kPa). The results suggest that the wetting front advancing velocity decreased as the vertical stress increased during infiltration, which indicates that the stress changes the infiltration channel and affects the infiltration rate. On the other hand, due to the water sensitivity of intensely weathered sandstone, the soil column deformation before and after wetting is significantly different, indicating that water infiltration further exacerbates the deformation. When vertical stress is applied to the soil column, the permeability coefficient–suction curves at different sections are paralleled in general, which is affected by the variation in dry density and the non-uniform distribution of stresses inside the soil column. Moreover, as the initial dry density increases, the influence of the vertical stress on the permeability coefficient gradually decreases.
Coupled thermo-hydro-mechanical-chemical modeling of fines migration in hydrate-bearing sediments with CFD-DEM
Authors: Liu Yajing , Wang Lizhong , Hong Yi , Yin Zhen-Yu
Published: November 2022

Fines migration associated with the multiphase flow in the exploitation of hydrate-bearing sediments (HBS) usually induces local clogging and sand production around wells, and thus its behavior with multi-field coupling is of vital importance but still poorly discovered. This paper establishes a coupled thermo-hydro-mechanical-chemical (THMC) model incorporating fines migration in HBS from micro- to macro-scale. Two typical hydrate pore habits, i.e., grain coating and pore filling, are simulated with the discrete element method (DEM) under different depressurization modes, water flow is simulated using computational fluid dynamics (CFD), and heat transfer and chemical reactions are also considered in coupled CFD-DEM simulations. Two distinct fines migration modes and their consequence on the mechanical and hydromechanical properties are revealed. For the grain-coating habit, the coarse particle size reduction induced by hydrate dissociation under an intense depressurization decreases the constriction size, increasing the local pore-clogging probability and reducing the growth rate of the hydraulic conductivity. Conversely, the fine particle size reduction in the pore-filling habit facilitates fines migration and thus sand production, with hydromechanical properties of HBS evolving oppositely compared to the clogging case.
Eimeria infection-related intestinal dynamics and microbiome, growth performance, and nutrient utilization in broiler chickens fed diets supplemented with multienzyme
Authors: Yuan Jing , Johnson Timothy A. , Ajuwon Kolapo M. , Adeola Olayiwola
Published: November 2022

Coccidiosis is an infectious parasitic disease. Increasing drug resistance and variable vaccine effectiveness have stimulated interests in developing alternate control strategies. Our research studied the effects of dietary supplementation of multienzyme (phytase, xylanase, β-glucanase, amylase, hemicellulase, and pectinase) in broiler chickens infected with coccidial pathogens by assessing ( i) nutrient utilization, immunological response, and gut health-related indicators in small intestine; and ( ii) intestinal microbiome modulations. One-day-old male Ross 708 chicks were assigned to 4 treatments in a 2 × 2 factorial arrangement comprising of 0 or 50 g·kg−1 multienzyme and oral challenge with phosphate buffer saline or mixed Eimeria spp. oocysts (250 000 E. acervulina, 50 000 E. maxima, and 50 000 E. tenella). Multienzyme reduced ( P < 0.05) Eimeria-induced loss in feed efficiency and nutrient utilization, partially explained by reduced decrease of b0,+ amino acid transporter in jejunum. Multienzyme suppressed ( P < 0.05) the overexpression of interleukin-8 in duodenum and jejunum and ameliorated ( P = 0.05) the decreased expression of antioxidant heme oxygenase 1 in ileum induced by Eimeria infection. Multienzyme facilitated ( P < 0.01) the bloom of short-chain fatty acid-producing and fiber-degrading microbes. Multienzyme supplementation partly mitigated the adverse effects of Eimeria infection through multiple mechanisms: improving nutrient utilization, reducing local inflammation, and restoring microbial homeostasis.
Strong Menger Connectivity of Folded Hypercubes with Faulty Subcube
Authors: Ma Meijie , Guo Chaoming , Li Xiang-Jun
Published: November 2022

Menger-type problems in interconnection networks have received many attentions in recent years. A connected graph [Formula: see text] is strong Menger (edge) connected if there are [Formula: see text] vertex (edge)-disjoint paths joining any two distinct vertices [Formula: see text] and [Formula: see text] in [Formula: see text]. Fault tolerance is an important criterion in the design of interconnection networks. The folded hypercube [Formula: see text] is an important variant of hypercube [Formula: see text] which remains many desirable properties of hypercube. We consider the strong Menger connectivity of folded hypercubes when part of the network is faulty. We show that [Formula: see text] [Formula: see text] is strong Menger (edge) connected. Which means that when a subcube [Formula: see text] is faulty, the surviving graph [Formula: see text] is strong Menger (edge) connected. This generalizes the result of [Formula: see text] in [J. Parallel Distrib. Comput. 138 (2020) 190–198].
Nanotechnology-Based Drug Delivery System for Anticancer Active Ingredients from Traditional Chinese Medicines: A Review
Authors: Liu Mengmeng , Chen Xinmei , Chen Hang , Wu Xin , Fan Wei , Chen Jianming
Published: November 2022

The variable dosage forms of most traditional Chinese medicines (TCMs) could be disadvantaged by low selectivity, poor biological distribution, limited bioavailability with low efficacy, and some adverse effects. These issues limit the control of clinical pharmacodynamics of the antitumor active components. With the progress of science and technology, many new polymer materials and new technologies have emerged, such as nanotechnology, cyclodextrin inclusion, solid dispersion, microcapsule and microsphere technologies. These new technologies provide a good basis for exploring novel TCM dosage forms for overcoming the shortcomings. The increased numbers of new technologies have been used to study TCM dosage forms with remarkable achievements. In this review paper, we will provide a systematic overview of the new dosage forms of nano-formulations and co-medications in relation to nano-delivery systems in an attempt to provide useful references for practical application of active antitumor ingredients from the TCMs.
A STUDY ON MULTI-STIRLING NUMBERS OF THE FIRST KIND
Authors: MA YUANKUI , KIM DAE SAN , LEE HYUNSEOK , PARK SEONGHO , KIM TAEKYUN
Published: November 2022

In this paper, we define the multi-Stirling numbers of the first kind by means of the multiple logarithm and as a generalization of the Stirling numbers of the first kind. Then we introduce two additional special numbers by using the multiple logarithm, namely the modified multi-Bernoulli numbers as a generalization of the higher-order Bernoulli numbers and the multi-Lah numbers of type 2 as a generalization of the Lah numbers. For both of these special numbers, we derive explicit expressions for them which involve the multi-Stirling numbers of the first kind.
Household’s Agricultural Vulnerability to Climate Induced Disasters: A Case on South-West Coastal Bangladesh
Authors: Khan Md. Ayatullah , Kabir Kazi Humayun , Hasan Kamrul , Sultana Rashmia , Al Imran Sardar , Karmokar Sanju
Published: November 2022

Climate change-related catastrophic events have a considerable influence on south-western coastal agriculture in Bangladesh. The objectives of this study are to measure the agricultural vulnerability of south-western coastal households in Bangladesh due to climate-induced disasters and to find the sub-indicators of adaptive capacity (AC) that influence the agricultural vulnerability. An agricultural vulnerability index (AVI) was developed by using the intergovernmental panel on climate change (IPCC) dimensions to measure the vulnerability. The sub-indicators of AC that affect agricultural vulnerability to climate-induced disasters were identified using an ordered logit model. This study employed a survey of 346 households from two villages (181 households from Sutarkhali and 165 households from Nalian) of the Sutarkhali Union of Dacope Upazila within a south-west coastal district (Khulna) of the country. The main respondents were the household heads. The findings demonstrated that Sutarkhali had a mean score of 0.703 (high) for exposure, 0.762 (high) for sensitivity, 0.397 (low) for AC, and 0.689 for AVI (high). Similarly, Nalian scored 0.658 (high) for exposure, 0.681 (high) for sensitivity, 0.410 (low) for AC, and 0.643 (high) for AVI. Non-farm employment, livestock ownership, irrigation pump access, improved crop diversification/saline tolerant high-yielding variety (HYV) crops access, and farm credit access were found to be statistically significant sub-indicators of AC that affect the agricultural vulnerability of both study sites. Finally, it is recommended that the relevant authorities and policy makers should implement the necessary agricultural adaptation initiatives in south-west coastal Bangladesh.
Structural core observations in a siliciclastic reservoir-scale framework
Authors: Fossen Haakon
Published: November 2022

Detailed knowledge of subseismic structures and their influence on reservoir production performance is important for optimal reservoir management. Predicting subseismic structures from seismic-scale structural interpretations is inherently difficult without the use of core data. Cores allow direct measurements of porosity and permeability of deformed rocks and enable researchers to make detailed investigation of deformation mechanisms and cementation processes. Frequency, distribution and sometimes orientation of planar structures can be constrained. Such observations are then used together with location relative to seismically mapped fault and fold structures, and with respect to lithology and stratigraphy. However, a significant gap exists between the scale of core observation and the size of structures mappable from seismic data. Bridging this gap requires a sound general understanding of the different structures that occur in reservoirs, which, in addition to faults, includes drag folds, veins, fractures and the many types of deformation bands that can exist in porous rocks. Proper understanding of such subseismic structures is primarily based on outcrop-based observations and analyses, aided by physical experiments and numerical modelling. We stress that integrating such cutting-edge knowledge with core, seismic and other case-specific subsurface data in an appropriate tectonic context is paramount for realistic reservoir characterization and successful reservoir management.
On the Need for Large Quantum Depth
Authors: Chia Nai-Hui , Chung Kai-Min , Lai Ching-Yi
Published: November 2022

Near-term quantum computers are likely to have small depths due to short coherence time and noisy gates. A natural approach to leverage these quantum computers is interleaving them with classical computers. Understanding the capabilities and limits of this hybrid approach is an essential topic in quantum computation. Most notably, the quantum Fourier transform can be implemented by a hybrid of logarithmic-depth quantum circuits and a classical polynomial-time algorithm. Therefore, it seems possible that quantum polylogarithmic depth is as powerful as quantum polynomial depth in the presence of classical computation. Indeed, Jozsa conjectured that “

Any quantum polynomial-time algorithm can be implemented with only
O
(log
n
) quantum depth interspersed with polynomial-time classical computations.

” This can be formalized as asserting the equivalence of
BQP
and “

BQNC
BPP

.” However, Aaronson conjectured that “

there exists an oracle separation between
BQP
and

BPP
BQNC

.

”

BQNC
BPP

and

BPP
BQNC

are two natural and seemingly incomparable ways of hybrid classical-quantum computation.

In this work, we manage to prove Aaronson’s conjecture and in the meantime prove that Jozsa’s conjecture, relative to an oracle, is false. In fact, we prove a stronger statement that for any depth parameter
d
, there exists an oracle that separates quantum depth
d
and 2
d
+1 in the presence of classical computation. Thus, our results show that relative to oracles, doubling the quantum circuit depth does make the hybrid model more powerful, and this cannot be traded by classical computation.
High-Fidelity Face Reenactment Via Identity-Matched Correspondence Learning
Authors: Xue Han , Ling Jun , Tang Anni , Song Li , Xie Rong , Zhang Wenjun
Published: November 2022

Face reenactment aims to generate an animation of a source face using the poses and expressions from a target face. Although recent methods have made remarkable progress by exploiting generative adversarial networks, they are limited in generating high-fidelity and identity-preserving results due to the inappropriate driving information and insufficiently effective animating strategies. In this work, we propose a novel face reenactment framework that achieves both high-fidelity generation and identity preservation. Instead of sparse face representations (e.g., facial landmarks and keypoints), we utilize the Projected Normalized Coordinate Code (PNCC) to better preserve facial details. We propose to reconstruct the PNCC with the source identity parameters and the target pose and expression parameters estimated by 3D face reconstruction to factor out the target identity. By adopting the reconstructed representation as the driving information, we address the problem of identity mismatch. To effectively utilize the driving information, we establish the correspondence between the reconstructed representation and the source representation based on the features extracted by an encoder network. This identity-matched correspondence is then utilized to animate the source face using a novel feature transformation strategy. The generator network is further enhanced by the proposed geometry-aware skip connection. Once trained, our model can be applied to previously unseen faces without further training or fine-tuning. Through extensive experiments, we demonstrate the effectiveness of our method in face reenactment and show that our model outperforms state-of-the-art approaches both qualitatively and quantitatively. Additionally, the proposed PNCC reconstruction module can be easily inserted into other methods and improve their performance in cross-identity face reenactment.
DPIVE: A Regionalized Location Obfuscation Scheme with Personalized Privacy Levels
Authors: Zhang Shun , Lan Pengfei , Duan Benfei , Chen Zhili , Zhong Hong , Xiong Neal N.
Published: November 2022

The popularity of cyber-physical systems is fueling the rapid growth of location-based services. This poses the risk of location privacy disclosure. Effective privacy preservation is foremost for various mobile applications. Recently, geo-indistinguishability and expected inference error are proposed for limiting location leakages. In this article, we argue that personalization means regionalization for geo-indistinguishability, and we propose a regionalized location obfuscation mechanism called DPIVE with personalized utility sensitivities. This substantially corrects the differential and distortion privacy problem of the PIVE framework proposed by Yu et al. on NDSS 2017. We develop DPIVE with two phases. In Phase I, we determine disjoint sets by partitioning all possible positions such that different locations in the same set share the Protection Location Set (PLS). In Phase II, we construct a probability distribution matrix in which the rows corresponding to the same PLS have their own sensitivity of utility (PLS diameter). Moreover, by designing a QK-means algorithm for more search space in 2-D space, we improve DPIVE with a refined location partition and present fine-grained personalization, enabling each location to have its own privacy level endowed with a customized privacy budget. Experiments with two public datasets demonstrate that our mechanisms have the superior performance, typically on skewed locations.
Diagnose Like Doctors: Weakly Supervised Fine-Grained Classification of Breast Cancer
Authors: Tian Jieru , Wang Yongxin , Chen Zhenduo , Luo Xin , Xu Xinshun
Published: November 2022

Breast cancer is the most common type of cancers in women. Therefore, how to accurately and timely diagnose it becomes very important. Some computer-aided diagnosis models based on pathological images have been proposed for this task. However, there are still some issues that need to be further addressed. For example, most deep learning based models suffer from a lack of interpretability. In addition, some of them cannot fully exploit the information in medical data, e.g., hierarchical label structure and scattered distribution of target objects. To address these issues, we propose a weakly supervised fine-grained medical image classification method for breast cancer diagnosis, i.e., DLD-Net for short. It simulates the diagnostic procedures of pathologists by multiple attention-guided cropping and dropping operations, making it have good clinical interpretability. Moreover, it cannot only exploit the global information of a whole image, but also further mine the critical local information by generating and selecting critical regions from the image. In light of this, those subtle discriminating information hidden in scattered regions can be exploited. In addition, we also design a novel hierarchical cross-entropy loss to utilize the hierarchical label information in medical images, making the classification results more discriminative. Furthermore, DLD-Net is a weakly supervised network, which can be trained end-to-end without any additional region annotations. Extensive experimental results on three benchmark datasets demonstrate that DLD-Net is able to achieve good results and outperforms some state-of-the-art methods.
STAD-GAN: Unsupervised Anomaly Detection on Multivariate Time Series with Self-training Generative Adversarial Networks
Authors: Zhang Zhijie , Li Wenzhong , Ding Wangxiang , Zhang Linming , Lu Qingning , Hu Peng , Gui Tong , Lu Sanglu
Published: November 2022

Anomaly detection on multivariate time series (MTS) is an important research topic in data mining, which has a wide range of applications in information technology, financial management, manufacturing system, and so on. However, the state-of-the-art unsupervised deep learning models for MTS anomaly detection are vulnerable to noise and have poor performance on the training data containing anomalies. In this article, we propose a novel Self-Training based Anomaly Detection with Generative Adversarial Network (GAN) model called STAD-GAN to address the practical challenge. The STAD-GAN model consists of a generator-discriminator structure for adversarial learning and a neural network classifier for anomaly classification. The generator is learned to capture the normal data distribution, and the discriminator is learned to amplify the reconstruction error of abnormal data for better recognition. The proposed model is optimized with a self-training teacher-student framework, where a teacher model generates reliable high-quality pseudo-labels to train a student model iteratively with a refined dataset so that the performance of the anomaly classifier can be gradually improved. Extensive experiments based on six open MTS datasets show that STAD-GAN is robust to noise and achieves significant performance improvement compared to the state-of-the-art.
Semantic Completion and Filtration for Image–Text Retrieval
Authors: Yang Song , Li Qiang , Li Wenhui , Li Xuan-Ya , Jin Ran , Lv Bo , Wang Rui , Liu Anan
Published: November 2022

Image–text retrieval is a vital task in computer vision and has received growing attention, since it connects cross-modality data. It comes with the critical challenges of learning unified representations and eliminating the large gap between visual and textual domains. Over the past few decades, although many works have made significant progress in image–text retrieval, they are still confronted with the challenge of incomplete text descriptions of images, i.e., how to fully learn the correlations between relevant region–word pairs with semantic diversity. In this article, we propose a novel semantic completion and filtration (SCAF) method to alleviate the above issue. Specifically, the text semantic completion module is presented to generate a complete semantic description of an image using multi-view text descriptions, guiding the model to explore the correlations of relevant region–word pairs fully. Meanwhile, the adaptive structural semantic matching module is presented to filter irrelevant region–word pairs by considering the relevance score of each region–word pair, which facilitates the model to focus on learning the relevance of matching pairs. Extensive experiments show that our SCAF outperforms the existing methods on Flickr30K and MSCOCO datasets, which demonstrates the superiority of our proposed method.
Al-Rich Primer for Al Alloy: Electrochemical and Computational Investigation
Authors: Upadhyay Vinod , Mendez Julio , Palani Siva , Legg Keith , Rose Alan
Published: November 2022

Analogous to Zn-rich primer for steel substrate, Al-rich primer is currently being investigated for their efficiency in protecting Aluminum based substrates. Various such primer systems were prepared with varying pigment size, with and without surface treatment. Electrochemical measurements such as open circuit potential, electrochemical impedance spectroscopy, and potentiostatic experiments were performed to obtain primer efficiency, such as throwing power and protection longevity. Data from electrochemical experiments will be used as boundary conditions and input parameters for computational modeling of the primer systems to investigate if results obtained from electrochemical measurements is complemented by computational results.
(Digital Presentation) The Role of Mg in Cut-Edge Corrosion Protection of 55 Mass% Al-Zn-Mg Coated Steel Under a Wet-Dry Cyclic Condition
Authors: Sugawara Yu , Ebina Ko , Suga Takumi , Fujii Takashi , Ueda Kohei
Published: November 2022

Pre-painted hot-dip 55 mass% Al-Zn coated steel sheets are widely used as a building material due to their superior corrosion resistance. In consideration of its long-term service, a pre-painted hot-dip 55 mass% Al-Zn-2 mass% Mg coated steel sheet with enhanced corrosion resistance has been developed in recent years.1 It has been shown that the addition of 2 mass% Mg not only reduced the corrosion rate by 1/3 but also inhibited the delamination of organic paints from the cut-edge. As yet, however, the role of Mg in the cut-edge corrosion protection of the 55 mass% Al-Zn-2 mass% Mg coated steel has not been completely clear. In this study, we focused on the influence of Mg-containing corrosion products on the electrochemical properties of the coating layer and the steel substrate.

Hot-dip 55 mass% Al-Zn-2 mass% Mg-1.6 mass% Si and 55 mass% Al-Zn-1.6 mass% Si coated steel sheets were used in this study. The Al-Zn-Mg coating layer is composed of Al-rich, Zn-rich, and Mg-Si phases. Our previous study has reported that for the Al-Zn-Mg coating layer, the Zn-rich phase preferentially dissolves during the initial process of cut-edge corrosion.2 In addition, Mg also preferentially dissolves from the Mg-Si phase in the Al-Zn-Mg coating layer.

The wet and dry cyclic corrosion test showed that the formation of the Zn-based corrosion products at the cut-edge for the Al-Zn-Mg coated steel was more inhibited than that for the Al-Zn coated steel. In addition, the sacrificial corrosion protection ability of the Al-Zn-Mg coated steel was higher than the Al-Zn coated steel. It was found that the dense corrosion products including Mg were formed on the steel substrate at the cut-edge for the Al-Zn-Mg coated steel 1 hour after the onset of the corrosion test. The Mg-containing corrosion products slightly reduced the cathodic current for the oxygen reduction reaction, and this is thought to be one of the factors for the improved cut-edge corrosion resistance.

1) N. Shimoda, Y. Morimoto, Y. Kubo, S. Fujii, and S. Shiragaki, Galvatech 2015 Proceedings, 802 (2015).

2) S. Tokuda, I. Muto, Y. Sugawara, M. Takahashi, M Matsumoto, and N. Hara, Corros. Sci, 129, 126 (2017).
Investigation of the Hydrogen Ingress and Embrittlement Induced By Corrosion of API 5L Natural Gas Pipeline Steels
Authors: Teeter Lucas , Rozman Kyle , Belarbi Zineb , Dogan Omer
Published: November 2022

Internal corrosion of natural gas pipelines is a major cause of many related accidents. In addition to the metal loss due to corrosion, hydrogen ions produced during corrosion can lead to the degradation of ductility of metals used in these pipelines. The effect of hydrogen generated through internal corrosion on current pipeline steels was studied. Three grades of API 5L steels commonly used in natural gas infrastructure were investigated: X56, X65, and X100. The rates of hydrogen diffusion were determined electrolytically via a Devanathan-Stachurski cell. The steels were subjected to hydrogen embrittlement tests using electrolytic hydrogen charging and constant strain rate tensile tests. The microstructure analysis of the investigated materials and the fracture surfaces was performed via scanning electron microscopy (SEM). This presentation reports on work to extend the life of the natural gas pipeline network via understanding the mechanisms of hydrogen ingress and subsequent embrittlement induced by corrosion processes.
On the Optimization of a Photo-Electrode: Interplay of Photoactive and Conductive Materials in a Lithium-Ion Photo-Battery
Authors: Briqueleur Elsa , Dollé Mickaël , Skene Will
Published: November 2022

Green and sustainable devices that can harvest and store the solar energy along with delivering electricity during dark periods have garnered much attention. This is owing to solar energy being the best renewable source of energy for producing clean electricity that can potentially meet demand on a global scale.

Although silica solar panels can harvest sunlight, they must be coupled with conventional batteries such as lithium ion batteries (LIBs) to store the collected energy. Organic dyes offer many advantages to silica panels. They are lighter, cheaper, more versatile, as well as a more sustainable harvesting solution. We therefore took advantages of the benefits of LIBs and an organic dye to lay the groundwork required for developing an all-in-one device that potentially can harvest sunlight and store the energy directly in the LIB.

An organic dye was judiciously selected based on its known properties that meet the requirements for light harvesting and charge transfer with the LIB active components. We have established structure/property relationships that have confirmed the dye can be reduced by the battery’s electroactive components upon light absorption. This will be complemented by steady-state and time-resolved solid-state emission quenching studies. It will be shown that Raman spectroscopy can provide further insight in the effect of the photobattery architecture and the conductive surfaces on the charge transfer processes. This will be complemented with electrochemical studies, including galvanostatic cycling with the dye with various photo-cathode architectures to further understand the role of the microstructure in the electronic transfer. Systematically replacing various components of the LIB with their organic counterparts will also be presented to elucidate the photocharge mechanisms and lay the groundwork for an all-in-one photobattery.
Repassivation Temperature of One-Dimensional Artificial Pits in Stainless Steel
Authors: Li Tianshu , Frankel Gerald S.
Published: November 2022

A new framework has been developed in recent works to describe pit growth stability 1-8, based on which many critical scientific issues in localized corrosion were addressed, such as the rate-controlling step in pit growth, the salt film growth and self-regulating mechanism, and the kinetics and the activation energy of metal dissolution in the local pit environment. Although many new insights were generated, there are still some phenomena that are not well understood, such as the pit repassivation temperature (T
rp). According to the new framework, T
rp is predicted to decrease with the increase of applied potential (E
app). However, T
rp sometimes exhibits an unexpected dependence on E
app that contradicts with the prediction, and the underlying mechanism is not clear.

In this study, T
rp of one-dimensional artificial pits made from 316L stainless steel was investigated in 3.5 wt.% NaCl by downward temperature scanning. For a given pit depth, T
rp exhibits an unexpected “S” dependence on applied potential, which has never been reported previously. Further analysis shows that this relationship is derived from repassivation underneath the salt film, which is different from repassivation that occurs when the pit surface concentration decreases below a critical value. This indicates that there is a reversal of the effect of the salt film on pit growth stability. The systematic study shows that such a reversal depends on temperature, E
app, and pit depth.

Acknowledgments: This work was supported as part of the Center for Performance and Design of Nuclear Waste Forms and Containers, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences under Award # DE-SC0016584.

References

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164 (4), C180-C181 (2017).

T. Li, J. R. Scully, and G. S. Frankel, Journal of The Electrochemical Society,
165 (9), C484-C491 (2018).

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165 (11), C762-C770 (2018).

T. Li, J. R. Scully, and G. S. Frankel, Journal of The Electrochemical Society,
166 (6), C115-C124 (2019).

T. Li, J. R. Scully, and G. S. Frankel, Journal of The Electrochemical Society,
166 (11), C3341-C3354 (2019).

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182 109277 (2021).

T. Li, J. Wu, X. Guo, A. M. Panindre, and G. S. Frankel, Corrosion Science,
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Critical Crevice Temperature – an Electrolyte Modeling Perspective
Authors: Sridhar Narasi , Anderko Andrzej
Published: November 2022

Critical pitting and crevice temperatures have been measured for many alloys using open-circuit potential tests in standard electrolytes, such as the 10 % FeCl3 or mixtures of NaCl with FeCl3 and CuCl2 for many years. Although these measurements are primarily used for alloy ranking purposes, there is interest in using them for applications with different solution chemistries. On the other hand, critical pitting temperature has been modeled in terms of the threshold condition for the formation of metal-chloride salt film or the maintenance of a critical metal-chloride concentration in the pit environment, using artificial pit electrodes and relatively simple solutions, such as NaCl. This paper addresses a modeling approach to bridge the gap between the immersion tests, electrochemical measurements, and theory. An irreversible thermodynamics model is combined with concentrated electrolyte speciation model to predict the critical crevice temperature of several Ni-Fe-Cr-Mo-W alloys. The model computes the repassivation and corrosion potentials of alloys as functions of solution composition and temperature. The superposition of these parameters provide a conservative estimate of the critical crevice corrosion temperature. The predicted values are validated against critical crevice temperature data reported in the literature. The effect of aqueous electrolyte composition on critical crevice temperature is calculated and compared to field experience. The model is further extended to mixed solvent systems, where the solvent is a non-aqueous environment. The implications of the model are discussed.
A Perspective on Environmentally Assisted Cracking
Authors: Latanision Ronald M
Published: November 2022

The premature mechanical failure of engineering alloys in practice is often associated with exposure to service environments. Such localized phenomena are described as environmentally-induced embrittlement or environmentally assisted cracking, EAC. These phenomena have been known for a very long time. Materials engineers are fully able to make materials selection decisions for the construction of engineering systems that see service in virtually any environment, though circumstances may sometimes lead to unintended exposure that becomes problematic. What is not known with certainty at this stage is the mechanism by which the various modes of EAC occur. The goal in this presentation is to assess the current state of knowledge of EAC, to identify what is known in a mechanistic sense and what remains to be understood in terms of the path forward toward a more complete mechanistic understanding.
(Digital Presentation) Effect of Mg2si on Trenching Formation Around Al6(Fe, Mn) on AA5083 in Diluted Synthetic Seawater
Authors: Kosaba Takumi , Muto Izumi , Nishimoto Masashi , Sugawara Yu
Published: November 2022

In chloride containing solutions like atmospheric environments, an interface between intermetallic particles (IMPs) and Al-matrix is mainly one of the initiation sites in localized corrosion of Al alloys. It has been widely reported that Al-matrix around IMPs containing Fe and/or Cu was dissolved like trenching due to the oxygen reduction reaction on the IMPs and the subsequent alkalization on and around the IMPs. The trenching is precursory stage of localized corrosion on Al alloys. In the case of AA5083, Al6(Fe, Mn) was known to become the initiation site of localized corrosion1). In addition to Al6(Fe, Mn), Mg2Si is precipitated in AA5083 to increase the mechanical strength. Mg in Mg2Si is easily dissolved to solutions immediately after immersion. Therefore, Mg2Si is less possible to become the initiation site of localized corrosion compared with Al6(Fe, Mn). For the reason, few previous research has clearly shown the effect of the Mg dissolution in Mg2Si on the trenching formation around Al6(Fe, Mn). In this study, the effect of Mg2Si on trenching formation around Al6(Fe, Mn) by immersion tests of microelectrode containing single or double IMPs.

A5083 (Al-Mg alloy) were prepared as specimen in this research. The four types of AA5083 electrodes (1. only Al6(Fe, Mn), 2. only Mg2Si, 3. both of Al6(Fe, Mn) and Mg2Si, 4. neither Al6(Fe, Mn) nor Mg2Si (Al-matrix on AA5083)) were prepared. Diluted synthetic seawater (200 mg/L Cl-, pH 8.2) was used as the electrolyte for immersion tests. Ag/AgCl (3.33 M KCl) was used as the reference electrode. The immersion time was 1 h.

After the immersion tests, trenching was generated around Al6(Fe, Mn) on microelectrode containing both of Al6(Fe, Mn) and Mg2Si. On the other hand, no trenching was observed around Al6(Fe, Mn) on microelectrode containing only Al6(Fe, Mn). The results suggested that the formation of trenching around Al6(Fe, Mn) was affected to Mg2Si.

1) T. Kosaba, I. Muto, and Y. Sugawara, J. Electrochem. Soc., 169, 020550 (2022). https://doi.org/10.1149/1945-7111/ac5301
(Digital Presentation) Effects of Secondary Phases in Stainless Steel on Corrosion Resistance
Authors: Saito Haruka , Muto Izumi , Nishimoto Masashi , Sugawara Yu
Published: November 2022

Stainless steels are widely used because of their high corrosion resistance. It is well known that Mo improves the pitting corrosion resistance of stainless steels1, 2).

Mo dissolves at the passive region of stainless steels because of transpassive dissolution. In this study, we tried to provide dissolved species of Mo into the solution by utilizing transpassive dissolution of Mo. The type 304L stainless steel containing Mo phases was fabricated and corrosion resistance was measured. For fabrication of samples, Spark Plasma Sintering (SPS) was used because non-equilibrium microstructure can be obtained by short sintering time and low temperature.

Type 304L stainless steel containing Mo phases was fabricated by SPS of type 304L gas atomized powder and 2.5 mass% of Mo powder. Sintering temperature was 1100℃ and it kept for 20 min. The specimen surface was polished down to 1 μm using a diamond paste. The same procedure was applied for fabricating sintered type 304L as comparison material.

The as-polished and etched surfaces of the samples were observed by an optical microscope. A field emission scanning electron microscope equipped with an energy-dispersive X-ray spectroscopy system was also used to observe the surface of the samples.

From the observation of sample surface, it was found that the samples contained many voids. Mo phases were also observed in entire surface. In Mo phases, the concentration of Mo was more than 90 mass%, and other elements were hardly detected.

To assess the corrosion resistance, potentiodynamic polarization curves were measured in 0.1 M NaCl (pH 6.0). Electrode area was set from 100 µm × 100 µm to 5 mm × 5 mm depend on the measurement. Specimens were covered by epoxy resin except electrode area.

Polarization curve of the samples were unstable because of the presence of voids. In measurement of Type 304L (SPS), current density increased with increasing potential and no passivation was occurred. On the other hand, in the case of type 304L containing Mo phases (SPS), increase of dissolution currents was inhibited with dissolution of Mo phases. After polarization, the surfaces of the samples were observed. Mo phases were preferentially dissolved, but the possibility of improvement of pitting corrosion resistance by dissolved Mo species from Mo phases.

If the effect of dissolved species of Mo can be obtained by Mo oxide was investigated. The sample was fabricated by sintering of mixed powder of 304L and MoO3 powder. After the polarization measurement, no pitting was observed. This indicate that corrosion resistance was improved.

References;

Saito, I. Muto and Y. Sugawara, Mater.Trans., 61 (2020), 2248-2251

Nishimoto, I. Muto, Y. Sugawara, N. Hara, J.Electrochem.Soc., 166 (11), C3081-C3089
Waste Heat Driven Microporous-Carbon-Based Thermo-Electrochemical Cells
Authors: Ghimire Basanta , Sapkota Nawraj , Behlow Herbert , Bhattacharya Sriparna , Sabet Morteza , Misra Abha , Rao Apparao M.
Published: November 2022

Solid-state thermoelectrics have focused on thermal to electrical energy conversion for many decades. Nevertheless, the thermoelectric energy conversion efficiency is limited by the intrinsic coupling between material properties such as electrical conductivity and the Seebeck coefficient, which reduces its efficiency despite much progress in this field. Here, we demonstrate a simple, cost-effective platform for harvesting waste heat into electricity via thermo-electrochemical cells (or thermocells) that utilize the effect of temperature on electrochemical redox potentials (i.e., the electrochemical Seebeck effect). In our preliminary experiments, coin cell type thermocells were prepared using microstructured carbon electrodes, aqueous ferricyanide/ferrocyanide redox couple, and commercial polymer separators. The wettability of the electrodes was varied by changing the duration of reactive ion etching (RIE), which improved the power performance. The highest output power (~ 75 nW) was recorded for RIE time of 3 minutes with a load of 1 kΩ. Separately, we also tested thermocells using natural wood-derived cellulose as separator materials. The performance of our thermocells will be presented, and their ability to directly power small electronic devices will be discussed.