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Due to the advantages of adjustable pore size, easy surface modification, high biocompatibility, and so on, mesoporous silica nanoparticles (MSNs) have attracted significant attention. Moreover, they are widely used in the fields of biology and medical research, mostly focusing on drug and gene delivery and bioimaging. This review introduces several commonly used synthetic methods of MSNs and the latest progress of MSNs in tumor therapy and diagnosis, mainly including the study about modified MSNs as drug carriers and the application of MSNs in bioimaging. The deficiencies of MSNs’ application and prospects for its future clinical transformation are also discussed.

The critical role of electrical homogeneity in optimising electric-field breakdown strength (BDS) and energy storage in high energy density (0.7 − x)BiFeO3–0.3BaTiO3–xBi(Li0.5Nb0.5)O3 (BF–BT–xBLN) lead-free capacitors is demonstrated. The high BDS for bulk ceramics and multilayers (dielectric layer thickness ∼ 8 μm) of ∼260 and ∼950 kV cm−1, respectively, gives rise to record-performance of recoverable energy density, Wrec = 13.8 J cm−3 and efficiency, η = 81%. Under an electric field of 400 kV cm−1, multilayers are temperature stable up to 100 °C, frequency independent in the range 10−2 to 102 Hz, have low strain (

TaC dense ceramic layer on the surface of gray cast iron was prepared in situ using casting-heat treatment process. Phase composition, morphology, and element distribution of TaC dense ceramics were analyzed and determined using X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). The microstructure and crystal structure of Ta–TaC interface and TaC–Fe interface were studied using transmission electron microscopy (TEM), and TEM samples were prepared using focused ion beam (FIB) technique. Scratch test with progressively increasing load of 0–50 N was conducted on the surface of TaC dense ceramic layer. Single abrasive wear behavior of TaC dense ceramic layer was evaluated using microscopic morphology of scratch, friction curve, and acoustic emission curve. Results show that TaC dense ceramic layer on gray cast iron surface was obtained via in situ reaction of C atoms in gray cast iron with Ta atoms in tantalum plate. Dominant mechanism for TaC particle growth is the diffusion of C atoms into the octahedral gap of Ta, and growth direction of TaC particles is the normal direction of Ta plate. TaC dense ceramic layer with a thickness of 20 μm can carry critical load of 48.7 N. The critical compressive stress of TaC dense ceramic layer on the gray cast iron matrix is estimated to be 302.08 MPa by theoretical calculation. The plastic deformation of TaC dense ceramic occurs before critical load of 48.7 N, and brittle fracture occurs after critical load of 48.7 N. The single abrasive wear form of TaC dense ceramic is the cutting wear.

The sulfonic acid group exhibits considerable ion affinity. The present work therefore synthesizes, a core-shell composite material having a sulfonated polyaniline shell, and a bamboo-derived porous carbon core loaded with sulfur. The thin, homogeneous shell has a thickness of approximately 20 nm. This composite is employed as a cathode material in Li-S batteries and the electrochemical properties of these devices are systematically investigated. This cathode (containing 64.0 wt% S) exhibits a higher initial discharge capacity (1484 mAh g−1 at 0.1 C), improved cycling stability (853 mAh g−1 after 100 cycles at 0.1 C), and remarkable rate performance (810.2, 682.7 and 353.0 mAh g−1 at 2, 3 and 5 C, respectively). These values are superior to those obtained using a polyaniline shell. Electrochemical impedance spectroscopy and density functional theory calculations are used to elucidate the internal mechanisms of the sulfonated polyaniline shell during cycling. The calculated results demonstrate that the shell possesses extremely high electron and Li ion conductivities, and so enhances the redox reaction kinetics during long-term cycling. It also physically confines and chemically anchors polysulfides, thus limiting the shuttle effect. This cathode design is expected to assist in the future commercialization of Li-S batteries.

In order to improve the friction and wear properties of gray cast iron surface, TaC ceramic layer was prepared by in-situ casting-heat treatment. TaC ceramic layer was analyzed by XRD, SEM and EDS. Hardness of the TaC layer was obtained by nanoindentation. Under the loading of 20 N at room temperature, the friction coefficient values, the wear rate and the wear weight loss of TaC layer were 0.17, 11.3 × 10−5 mm3/Nm and 2.4 mg, respectively. At room temperature, the wear mechanism is dominated by abrasive wear at low load (5 N, 10 N, 15 N), the abrasive wear and slight adhesive wear at high load (20 N). The wear form of TaC layer can be divided into three categories according to the temperature changes.

It had been proven that carbon aerogel (CA) can effectively improve the conductivity of sulfur (S) and suppress the shuttle effect of polysulfides in Li-S batteries, due to its outstanding electrical conductivity and micropore-rich structure. However, the microstructure of CA was easy to collapse and shrink during carbonization, resulting in a dramatically drop in specific surface area and porosity. Herein, graphene nanosheets (GNs) were introduced in CA to reinforce the structural stability. As-prepared CA/GNs composites were fabricated from in-situ polymerization of resorcinol (R) and formaldehyde (F) in graphene oxide (GO) solution. It was found that the mass concentration of the GO solution had a significantly positive effect on hierarchical porous structure of the CA/GNs composites, which presented improve the electrochemical performances due to the combination of micro-, meso- and macro-pores. It is worth noting that the CA/GNs0.1 sample, obtained from 10 wt % GO solution, possessed the largest specific surface area of 665.477 m2 g−1 and the largest pore volume of 0.912 cm3 g−1. Especially, after incorporated with moderate amount of S (58.86 wt %), the CA/GNs0.1/S cathode exhibited the best electrochemical performances (initial discharging capacity of 1501 mAh g−1 at 0.1C and reversible capacities of 471 mAh g−1 after 100 cycles and 341 mAh g−1 after 500 cycles at 1C). This was attributed to the tunable hierarchical porous microstructure of the CA/GNs0.1 sample. Unfortunately, when increased the S content to 68.39 wt %, the electrochemical performance deteriorated in all aspects because of their sluggish reaction kinetics. These all results suggested that introducing GNs can feasibly enhance the performance of CA as matrix in Li-S batteries.

Lithium-sulfur (Li-S) battery with high theoretical capacity (1675 mAh g−1) and energy density (2600 Wh kg−1) is principally considered as an attractive alternative for state of art Li-ion batteries. In this study, a series of ternary composites were synthesized with bamboo-derived hierarchical carbon (BDC) to load S and flexible polyaniline (PANI) as a coating layer. The BDC/S composite was encapsulated by different weight percentage of PANI. The ternary PANI@BDC/S composites were characterized detailly by structural and electrochemical analysis and the results revealed that the PANI@BDC/S-20% electrode presented a thin and uniform PANI coating. As a cathode material for Li-S battery, the PANI@BDC/S-20% electrode exhibited the highest initial capacity (1463 mAh g−1 at 0.1C), outstanding long-life performance (366 mAh g−1 at 0.5C after 500 cycles), excellent rate property (527 mAh g−1 at 2C). The incremented gains were mainly because thin PANI coating was polymerized along with the porous carbon walls of BDC substrate, leaving an excellent hierarchical porous microstructure. The specific structure showed great physical confinement for polysulfides, meantime, the polysulfide migration could be restricted by heteroatom (N atom) doped on the PANI backbone. The soft and stable PANI shell reduce volume expansion during cycles, providing an integrated conductive framework for enhancing the electrochemical contact between S particles and carbon substrate. More important, the modified polar interface contributed to stable SEI formation. Such a novel design of cathode material demonstrated great potential for practical applications in Li-S batteries.

Red blood cells (RBCs) are biocompatible carriers that can be employed to deliver different bioactive substances. In the past few decades, many strategies have been developed to encapsulate or attach drugs to RBCs. Osmotic-based encapsulation methods have been industrialized recently, and some encapsulated RBC formulations have reached the clinical stage for treating tumors and neurological diseases. Inspired by the intrinsic properties of intact RBCs, some advanced delivery strategies have also been proposed. These delivery systems combine RBCs with other novel systems to further exploit and expand the application of RBCs. This review summarizes the clinical progress of drugs encapsulated into intact RBCs, focusing on the loading and clinical trials. It also introduces the latest advanced research based on developing prospects and limitations of intact RBCs drug delivery system (DDS), hoping to provide a reference for related research fields and further application potential of intact RBCs based drug delivery system.

Lithium-sulfur (Li-S) battery processes high theoretical capacity (1675 mA h g−1) and energy density (2600 Wh kg−1), which was widely accepted as one of the most promising candidates for energy storage devices. In this presented study, bamboo-derived hierarchical porous carbon (BDPC) was adopted as a conducting substrate for containing S. Soft polystyrene (PS) and polyaniline (PANI), were prepared as coating layers. The main purpose is to figure out the specific roles that the polymer shells and the heteroatoms doped on polymer backbone play during cycles. The ternary products were characterized by structural analysis and electrochemical testing. The results indicate that, as compared to BDPC/S, the PS@BDPC/S electrode displays higher capacity retention during long-term cycles, especially at the high current rate. It is attributed to the integrated coating shell, which provides physical confinement and reserves spaces for restraining volume expansion. It is noted that the PANI@BDPC/S electrode presents a higher initial capacity, remarkable long-life performance, and excellent rate property. The outstanding performances are closely related to the nitrogen atom doped on PANI backbone, they provide not just abundant polar conducting sites for fast electron/Li-ion transport but strong chemical anchoring for restricting the migration of polysulfides. Therefore, our study poses a clearer understanding of the functionalized polymers used in Li-S battery.

A series of banana peels derived porous carbon (BPPC) materials were fabricated by pyrolysis carbonization with different numbers of KOH activation. The Brunauer–Emmett–Teller tests indicated the number of activation effectively improves the specific surface area and pore volume of the BPPC. Amongst, the BPPC-2 (activated twice) possesses ultrahigh specific surface area (2044.57 m2 g−1) and large pore volume (2.40 cm3 g−1) on account of the improved hierarchical porous microstructure. After S loading process, the resultant C/S composites were introduced as cathode material in Li–S batteries. The S/BPPC-2 composite cathode exhibited a higher initial specific capacity (1481.54 mAh g−1 at 0.1 C) and a better reversible capacity (351 mAh g−1 after 300 cycles at 1 C) than those of others. It also exhibited excellent high rate performance even at 5 C. The enhanced electrochemical performances were ascribed to the improved specific surface area and larger pore volume of the BPPC-2, which effectively facilitated the intimate contact between sulfur and the conductive matrix, accommodating severe volume change. Besides, the micro/mesopores provided high adsorption power to inhibit the dissolution of polysulfides. This research suggested that the activation number played a key role in improving the electrochemical performance of composite cathode in Li–S batteries.

Bamboo derived porous carbon materials, as inexpensive and environmentally friendly, microporous material sources, have been attracting enthusiastic attention for energy storage applications. In this work three different processes were employed to prepare three types of bamboo derived porous carbon materials. Among them, the sample prepared via a one-step activation method delivered the largest total pore volume (1.146 cm3 g−1) and the largest specific surface area (1824.4 m2 g−1) owning to a hierarchical porous structure. After the sample was used to encapsulate sulfur (S) to prepare carbon/S composite as cathodes for Li-S batteries. The composite loaded with 58.5 wt% S exhibited a high initial capacity of 1453 mAh g−1 at a rate of 0.1 C (1 C = 1675 mA g−1). A reversible capacity of 255 mAh g−1 was maintained after 500 cycles at 1 C with a capacity decay rate of only 0.0016% per cycle. This suggests that the bamboo derived porous carbon could be a promising conductive carbon matrix for carbon/S composite cathodes in Li–S batteries.

CaCO3-templating is a strategy for synthesizing porous carbon (PC) materials that has been widely used for decades. In this work, a modified template-removal process, soaking the pyrolysis product by hydrochloric acid solution, was proposed to optimize the graphitization degree, morphology, specific area, and pore size distribution of the products. The tests results demonstrated that the PC product obtained by a modified template method (M-TC) exhibited a transformation in microstructure such as an enhanced specific surface area and more plentiful hierarchical pores as compared with those PC materials obtained by conventional strategy. The potential formation mechanisms are proposed as well. When the M-TC sample loaded sulfur was applied as a cathode material for a Li-S battery, it delivered a high initial discharge capacity (1475 mAh g−1) and a stable discharge capacity (874 mAh g−1) after 50 cycles at 0.1 C. The modified template-removal strategy could bring inspirations on synthesis design and extend potential applications of commercial PC materials.

For Li-S batteries, commercial application was hindered by the insulating nature of S and the solubility of polysulfide. Porous carbon materials had proven themselves to be an ideal immobilizer host for S impregnation. Herein, carbon aerogels (CAs) with tunable pore microstructure were synthesized from resorcinol-formaldehyde reaction with increasing catalyst concentration and pyrolysis under high temperature. The results demonstrated that the catalyst concentration played a key role in tuning the porous microstructure of the CAs. In addition, potassium hydroxide (KOH) was introduced to activate the obtained CAs. The activated carbon aerogels (A-CAs) with hierarchical porous structure exhibited the highest specific surface area (1837.4 m2 g−1) and the largest total pore volume (2.276 cm3 g−1), which combined the advantages of both mesoporous and microporous. The effects of porous microstructure, specific surface area, and pore volume of the CAs and A-CAs on S incorporation were studied. The S/A-CAs exhibited significantly improved reversible capacity (1260 mAh g−1 at a rate of 0.1 C), enhanced high-rate property, and excellent cycling performance (229 mAh g−1 after 500 cycles at 1 C) as a cathode for Li-S batteries.

When almost eighty percent of the senior executives from 362 companies claimed they provided an exceptional customer experience, only eight percent of their customers agreed [1]. It is challenging and necessary to evaluate customer experiences in a proper way, especially under the Chinese cultural background. This paper describes the new application of the Wizard-of-Oz method aimed at exploring deep customer experience preferences. In the following article the authors illustrate the essence of customer experience and present the overview of the Wizard-of-Oz method across the sections. Furthermore the article details the practice of the Wizard-of-Oz experiment based on a development project of smartphone-based vehicle telematics services. Finally the article analyzes the results from the Wizard-of-Oz experiment in the form of sentiment trend matrix.

In this paper, the high volume fraction of NbC (Niobium carbide) reinforced layer was prepared on the surface of iron by in situ reaction method using grey cast iron and high-purity Nb plate as raw materials. The phase-composition, morphology, microstructure, nano-mechanical properties, and deformation mechanism of the enhancement layer under continuous small loads were investigated using x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nanoscratching. The results show that the average grain size of NbC in the high volume fraction of submicron structured NbC enhancement layer is about 255 ± 38 nm. The NbC ceramic particles are closely connected with each other, and the crystal grain size is uniform. The NbC ceramic layer volume fraction is approximately 95%. During the nanoscratch experiment under continuous small loads, the compact NbC ceramic layer followed the order 'elastic deformation -> plastic deformation -> cracking', and only occurs as shallow ploughing wear and slight grain spalling under 650 mN. The toughening mechanism of the enhancement layer include high-strength bonding between ceramic particles, reinforcing and toughening of the high hardness and high modulus of NbC enhanced phase, and strengthening of fine grains.