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Machines have continually developed with the needs of daily life and industrial applications. While the careful design of molecular‐scale devices often displays enhanced properties along with mechanical movements, controlling mechanics within solid‐state molecular structures remains a significant challenge. Here, we explore the distinct mechanical properties of zeolitic imidazolate frameworks (ZIFs)—frameworks that contain hidden mechanical components. Using a combination of experimental and theoretical approaches, we uncover the machine‐like capabilities of ZIFs, wherein connected composite building units operate similarly to a mechanical linkage system. Importantly, this research suggests that certain ZIF subunits act as core mechanical components, paving an innovative view for the future design of solid‐state molecular machines. [ABSTRACT FROM AUTHOR]

The utilization of Si anode in sulfide‐based all‐solid‐state batteries (ASSBs) has gained more research attention in recent years to overcome the interface challenges associated with ASSB‐containing Li metal anode. However, the volume expansion feature of the Si, stress/strain evolution inside the electrode, and the parasitic side reaction at the Si/sulfide SE interface are the most predominant limiting factors for practical device applications. It is necessary to investigate and understand the interface challenges through in‐depth analysis in real‐time battery operation to design highly efficient ASSBs for commercial device applications. Hence, this perspective paper provides a summary of the characterization tools and the analysis results related to the Si/sulfide SE interface. Moreover, in this perspective, we emphasize the importance of further investigation of the interface through more advanced in‐depth/operando analysis tools to gain insightful information about the anodic interface, which could be useful for the researchers to design efficient research strategies for solving the challenging issues associated with the anodic interface. [ABSTRACT FROM AUTHOR]

The increasing demand for electric vehicles (EVs) has prompted extensive research in the development of lithium-ion batteries (LIBs) with high volumetric energy density. The graphite anode possesses a tap density of 2.25 g cc−1, resulting in a volumetric energy density of over 770 W h L−1. However, the practical electrode density of 1.4–1.6 g cc−1 leads to a lower volumetric energy density of ∼550 W h L−1, and increasing electrode density beyond 1.6 g cc−1 is limited owing to the pore closure and poor electrolyte penetration, which leads to an imbalance in the N/P ratio resulting in Li metal plating. Hence, enhancing the electrolyte permeation into the densely packed graphite electrode is the crucial aspect for achieving high volumetric energy density. In this research, we coated a functional polymer (cyanoethyl polyvinyl alcohol), which has a high electrolyte absorption capability on a conventional graphite anode to enhance the electrolyte penetration into the highly densified graphite. As a result, the electrode demonstrated a high cycle stability under a high electrode density of 1.9 g cc−1 without any Li plating, and drastic degradation of capacity retention resulted in a remarkable volumetric energy density exceeding 650 W h L−1. [ABSTRACT FROM AUTHOR]

Obstructive pulmonary diseases, such as diffuse panbronchiolitis (DPB), asthma, chronic obstructive pulmonary disease (COPD), and asthma COPD overlap syndrome (ACOS) trigger a severe reaction at some situations. Detecting early airflow limitation caused by diseases above is critical to stop the progression. Thus, there is a need for tools to enable self-screening of early airflow limitation at home. Here, we developed a novel non-contact early airflow limitation screening system (EAFL-SS) that does not require calibration to the individual by a spirometer. The system is based on an infrared time-of-flight (ToF) depth image sensor, which is integrated into several smartphones for photography focusing or augmented reality. The EAFL-SS comprised an 850 nm infrared ToF depth image sensor (224 × 171 pixels) and custom-built data processing algorithms to visualize anterior-thorax three-dimensional motions in real-time. Multiple linear regression analysis was used to determine the amount of air compulsorily exhaled after maximal inspiration (referred to as the forced vital capacity, FVCEAFL–SS) from the ToF-derived anterior-thorax forced vital capacity (FVC), height, and body mass index as explanatory variables and spirometer-derived FVC as the objective variable. The non-contact measurement is automatically started when an examinee is sitting 35 cm away from the EAFL-SS. A clinical test was conducted with 32 COPD patients (27/5 M/F, 67–93 years) as typical airflow limitation cases recruited at St. Marianna University Hospital and 21 healthy volunteers (10/11 M/F, 23–79 years). The EAFL-SS was used to monitor the respiration of examinees during forced exhalation while sitting still, and a spirometer was used simultaneously as a reference. The forced expiratory volume in 1 s (FEV1%EAFL–SS) was evaluated as a percentage of the FVCEAFL–SS, where values less than 70% indicated suspected airflow limitation. Leave-one-out cross-validation analysis revealed that this system provided 81% sensitivity and 90% specificity. Further, the FEV1EAFL–SS values were closely correlated with that measured using a spirometer (r = 0.85, p < 0.0001). Hence, EAFL-SS appears promising for early airflow limitation screening at home.

CF4 plasma treatment is performed on commercial TiO2 to improve the photocatalytic efficiency. The CF4 plasma treatment is a facile and fast method for simultaneous introduction of carbon and fluorine atoms onto TiO2. Photodegradation of rhodamine B, methyl orange, and methylene blue is carried out under solar light irradiation to determine its CF4 plasma treatment effect. The dye removal of commercial TiO2 to rhodamine B, methyl orange, and methylene blue is 60.0, 18.9, and 49.2%, respectively, whereas TiO2 treated with CF4 plasma for 50 min is 93.5, 71.0, and 88.6% for rhodamine B, methyl orange, and methylene blue, respectively. In addition, the photodegradation rate constants of TiO2 treated with CF4 plasma for 50 min were 0.0135, 0.0083, and 0.0129 min−1 for rhodamine B, methyl orange, and methylene blue, respectively, which are up to 7.5 times higher than that of untreated TiO2 (0.0049, 0.0011, and 0.0039 min−1). This improvement is attributed to the increase in oxygen vacancies by the introduction of carbon atoms into TiO2 using CF4 plasma treatment. In addition, the F− ions physically adsorbed to the TiO2 surface promote the formation of hydroxyl free radicals, enabling effective decomposition of various dyes. [ABSTRACT FROM AUTHOR]

The front cover of the journal article "Recent Progress of In-Depth Analysis Techniques for Si Anodes in Sulfide-Based All-Solid-State Batteries: A Concise Overview and Future Perspective" features an image of the interface between the sulfide-based solid electrolyte and silicon anode in all-solid-state lithium-ion batteries. The image highlights the importance of studying the electrode/electrolyte interface in order to design high-energy batteries. The authors argue that more advanced analysis tools are needed to fully understand the interface kinetics and charge transport mechanism for developing efficient battery systems for electric vehicles and portable devices. The article provides further information on this topic. [Extracted from the article]

A location problem with stochastic demand and congestion where mobile servers respond to service calls originating from nodes is considered. The problem is of the set-covering type: only servers within the coverage radius of the demand-generating node may respond to a call. The service level constraint requires that at least one server must be available to respond to an arriving call, with some prespecified probability. The objective is to minimize the total number of servers. It is shown that earlier models quite often overestimate servers' availability and thus may lead to infeasible solutions (i.e., solutions that fail to satisfy the service level constraint). System stability conditions and lower bounds on system availability are developed by analyzing the underlying partially accessible queueing system. These lead to the development of two new models for which feasibility is guaranteed. Simulation-based computational experiments show that the proposed models achieve feasibility without significantly increasing the total number of servers. [Supplementary materials are available for this article. Go to the publisher's online edition of IIE Transactions for the following free supplemental resource: Appendix of Tables of Computational Results for Section 7.] Keywords: Location, network, queueing, congestion, 1. Introduction The fundamental problem facing emergency system planners can be described as follows. Customers residing at the nodes of a transportation network generate stochastic streams of service calls. These [...]

We consider the problem of locating a set of facilities on a network to maximize the expected number of captured demand when customer demands are stochastic and congestion exists at facilities. Customers travel to their closest facility to obtain service. If the facility is full (no more space in the waiting room), they attempt to obtain service from the next-closest facility not yet visited from its current position on the network. A customer is lost either when the closest facility is located too far away or all facilities have been visited. After formulating the model, we propose two heuristic procedures. We combine the heuristics with an iterative calibration scheme to estimate the expected demand rate faced by the facilities: this is required for evaluating objective function values. Extensive computational results are presented. Keywords: Location, congestion, optimization, queueing, 1. Introduction One of the most important objectives for profit and nonprofit organizations when locating service facilities in a geographical region is to capture as much potential customer demand as [...]