LiNi1–x–y Co x Al y O2 (NCA) and LiNi1–x–y Mn x Co y O2 (NMC) materials are widely used in electric vehicle and energy storage applications. Derived from LiNiO2, NCA and NMC materials with various chemistries were developed by replacing Ni with different cations. Many studies of the failure mechanisms of NCA and NMC materials have attributed the cell degradation to the anisotropic volume change of particles. In this work, it is shown that for Ni-rich layered transition metal oxide materials, regardless of composition, the unit cell volumes change in an almost identical manner during delithiation. Half-cell cycling data collected from 26 sets of Ni-rich materials with different compositions allow a relationship between capacity retention and accessible capacity to be observed. This relationship can be correlated to the change in unit cell volume during the lithiation–delithiation process. This work suggests a universal failure mechanism for Ni-rich positive electrode materials that must be overcome.

The web-services stack of standards is designed to support the reuse and interoperation of software components on the web. A critical step in the process of developing applications based on web services is service discovery, i.e. the identification of existing web services that can potentially be used in the context of a new web application. Discovery through catalog-style browsing (such as supported currently by web-service registries) is clearly insufficient. To support programmatic service discovery, we have developed a suite of methods that assess the similarity between two WSDL (Web Service Description Language) specifications based on the structure of their data types and operations and the semantics of their natural language descriptions and identifiers. Given only a textual description of the desired service, a semantic information-retrieval method can be used to identify and order the most relevant WSDL specifications based on the similarity of the element descriptions of the available specifications with the query. If a (potentially partial) specification of the desired service behavior is also available, this set of likely candidates can be further refined by a semantic structure-matching step, assessing the structural similarity of the desired vs the retrieved services and the semantic similarity of their identifiers. In this paper, we describe and experimentally evaluate our suite of service-similarity assessment methods.

One way to lower the cost of lithium ion batteries using LiNi x Mn y Co z O 2 (NMC) or LiNi 0.80 Co 0.15 Al 0.05 O 2 is to lower the Co content in the positive electrode materials. This work systematically studied the impact of the synthesis conditions on the performance of LiNi x Co y Al z O 2 (x ≥ 0.8, z ≤ 0.05 and x + y + z = 1) (NCA) with high Ni and low Co content. The impacts of oxygen flow rate, sintering temperature, initial Li/TM ratio and sintering time on the structural and electrochemical properties of NCA were systematically studied. The conditions when impurity phases such as Li 2 CO 3 and Li 5 AlO 4 appear were carefully examined. The impact of residual lithium compounds on the electrochemical performance was also discussed. It was found that the synthesis conditions, which affect the a-axis, c-axis and Ni Li content of the NCA samples, have strong impacts on the lithium diffusion at low and high states of charge based on differential capacity vs. voltage (dQ/dV vs. V) measurements at various rates and temperatures. Additionally, the reversible capacity and cycling stability correlated strongly with the intensity of the dQ/dV vs V peak at 3.5 V (discharge) measured with a C/20 rate at 30 • C.

Tackling the huge volume expansion of silicon (Si) anode desires a stable solid electrolyte interphase (SEI) to prohibit the interfacial side reactions. Here, a layered conductive polyaniline (LCP) coating is built on Si nanoparticles to achieve high areal capacity and long lifespan. The conformal LCP coating stores electrolyte in interlamination spaces and directs an in situ formation of LCP‐integrated hybrid SEI skin with uniform distribution of organic and inorganic components, enhancing the flexibility of the SEI to buffer the volume changes and maintaining homogeneous ion transport during cycling. As a result, the Si anode shows a remarkable cycling stability under high areal capacity (≈3 mAh cm−2) after 150 cycles and good rate performance of 942 mAh g−1 at 5 A g−1. This work demonstrates the great potential of regulating the SEI properties by a layered polymer‐directing SEI formation for the mechanical and electrochemical stabilization of Si anodes.

In the field of medicine, there are a large number of new drugs synthesis every year. Before entering the clinical stage, it needs a lot of work on drug testing of the various properties. Due to the lack of a large number of laboratory technician, laboratory equipment and reagents, the drug testing of many biochemical properties are not completed. Theoretical medicine provides a theoretical way for medical researchers to obtain the pharmaceutical properties of compounds by calculation tricks. In this paper, the first multiplication atom-bond connectivity index of several common drugs structure are studied, and the accurate expressions are determined. These theoretical conclusions provide practical guiding significance for pharmaceutical engineering.

This work studies the effect of Mg doping in LiMO 2 (M = Ni, Ni+Al, Ni+Co+Al, Ni content >0.8) at a dopant level of less than 5%. Synthesized materials were all single phase and contained no appreciable amount of surface or bulk impurities. Structural and electrochemical characterization of the materials was carried out to understand how Mg affects the materials and whether the presence of Al or Co influences the dopant effects of Mg. All synthesized materials, even those without Co, were found to contain a small amount of Ni in the Li layer. Increases in the Mg content of the material reduced the initial capacity of the materials but improved the capacity retention. The capacity reduction was related to the amount of Li trapped by electrochemically inactive Al and Mg. The capacity retention was related either to the number of Ni ions substituted by electrochemically inactive dopants or to the amount of Li trapped by those dopants. Mg helped improve capacity retention by reducing the growth of polarization during cycling. No synergistic effects were found to exist from co-doping materials containing Co and/or Al with Mg.

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The web-services stack of standards is designed to support the reuse and interoperation of software components on the web. A critical step in the process of developing applications based on web services is service discovery, i.e., the identification of existing web services that can potentially be used in the context of a new web application. UDDI, the standard API for publishing webservices specifications, provides a simple browsing-by-business-category mechanism for developers to review and select published services. To support programmatic service discovery, we have developed a suite of methods that utilizes both the semantics of the identifiers of WSDL descriptions and the structure of their operations, messages and data types to assess the similarity of two WSDL files. Given only a textual description of the desired service, a semantic information-retrieval method can be used to identify and order the most similar service-description files. This step assesses the similarity of the provided description of the desired service with the available services. If a (potentially partial) specification of the desired service behavior is also available, this set of likely candidates can be further refined by a semantic structure-matching step assessing the structural similarity of the desired vs. the retrieved services and the semantic similarity of their identifier. In this paper, we describe and experimentally evaluate our suite of service-similarity assessment methods.