Solvent-Resistant Wearable Triboelectric Nanogenerator for Energy-Harvesting and Self-Powered Sensors

Wearable triboelectric nanogenerators(TENGs)have attracted attention owing to their ability to harvest energy from the surrounding environment without maintenance.Herein,polyetherimide-Al_(2)O_(3)(PAl)and polyvinylidene fluoride-co-hexafluoropropylene(PVDF-HFP,PH)nanofiber membranes were used as tribo-positive and tribo-negative materials,respectively.Phytic acid-doped polyaniline(PANI)/cotton fabric(PPCF)and ethylenediamine(EDA)-crosslinked PAl(EPAl)nanofiber membranes were used as triboelectrode and triboencapsulation materials,respectively.The result showed that when the PAl-PH-based TENG was shaped as a circle with a radius of 1 cm,under the pressure of 50 N,and the frequency of 0.5 Hz,the open-circuit voltage(V_(oc))and short-circuit current(I_(sc))reached the highest value of 66.6 V and-93.4 to 110.1 nA,respectively.Moreover,the PH-based TENG could be used as a fabric sensor to detect fabric composition and as a sensor-inductive switch for light bulbs or beeping warning devices.When the PAl-PH-based TENG was shaped as a 5×5 cm^(2)rectangle,a 33 pF capacitor could be charged to 15 V in 28 s.Interestingly,compared to PAl nanofiber membranes,EPAl nanofiber membranes exhibited good dyeing properties and excellent solvent resistance.The PPCF exhibited<5%resistance change after washing,bending,and stretching.

Advanced Strategies to Improve Performances of Molybdenum-Based Gas Sensors

Molybdenum-based materials have been intensively investigated for high-performance gas sensor applications.Particularly,molybdenum oxides and dichalcogenides nanostructures have been widely examined due to their tunable structural and physicochemical properties that meet sensor requirements.These materials have good durability,are naturally abundant,low cost,and have facile preparation,allowing scalable fabrication to fulfill the growing demand of susceptible sensor devices.Significant advances have been made in recent decades to design and fabricate various molybdenum oxides-and dichalcogenides-based sensing materials,though it is still challenging to achieve high performances.Therefore,many experimental and theoretical investigations have been devoted to exploring suitable approaches which can significantly enhance their gas sensing properties.This review comprehensively examines recent advanced strategies to improve the nanostructured molybdenum-based material performance for detecting harmful pollutants,dangerous gases,or even exhaled breath monitoring.The summary and future challenges to advance their gas sensing performances will also be presented.

Effect of Garment Pressure on Peripheral Skin Blood Flow(SBF)

To well understand the effect of garment pressure on skin blood flow(SBF) at lower limb,external pressures of various magnitudes were exerted on lower limb in supine or sitting postures respectively using sphygmomanometer.Five male subjects volunteered to participate in this study.An alternating pressure loading protocol between non-pressure and pressure was employed.The SBF was observed by laser flowmeter.No matter the subjects being sitting or supine,SBF obviously increased under low pressure;as the pressure increasing,it turned to decrease.Moreover,while lying supine,SBF turned to decrease under lower pressure than sitting;SBF at calf turned to decrease under lower pressure than at ankle.It was also confirmed that the increment of SBF was obviously higher when the pressure of the same magnitudes was exerted at ankle than at calf.The pressure around 5.32 kPa was confirmed to be a crucial value to SBF.The findings will be helpful in design and application of tight-fit garments.

THE HANDLE OF SILK A STUDY BY THE SUBJECTIVE EVALUATION

The handle of silk fabrics and the feel having silk blouses on were studied by comparingwith those of polyester Shin-gosen fabrics and blouses. The subjective evaluation was carried bythe SD method. Factor analyses were processed to study the good feel with skin andcomfortableness on weaning.Generally the handle of silk and Sin-gosen fabrics was evaluatedbo be soft,pliable,smooth,slippery,thin and light,conclusively to give a good touch with handReferring to blouses,it was evaluated to be easy in motion, and nice in touch with skin and com-fortable upon weaning.Based on the result of thefactor analyses,it can be said that a blouse ingood touch with skin is pliable,soft,smooth,slippery,and easy to move. In addition,it has beenknown that "comfortableness" of a blouse upon weaning is largely influenced by the touch withskin. Further, the touch with skin was defined by the factors of softness, pliability, and smooth-ness on surface,and the factors of thickness, coolness and weight.

LATERAL DISPERSAL OF ADULT AQUATIC INSECTS FOLLOWING EMERGENCE FROM THE MIDDLE REACHES OF THE CHIKUMA RIVER(HONSHU ISLAND,JAPAN)IN RELATION TO WATERFRONT VEGETATION

To clarify the role of waterfront vegetation of floodplains for adult aquatic insects, Trichoptera and Diptera (Tipulidae and Chironomidae), in the middle reaches of the Chikuma River from May to July, an investigation of the number of these insects was conducted by trapping in each type of vegetation using board traps.A total of 2608.5 adults/m 2 were collected, and we identified a total of 26 species belonging to three taxa,i.e., seven species of Trichoptera, four species of Tipulidae and 15 species of Chironomidae. The most abundant species was Psychomyia acutipennis in Trichoptera (95.7%). There was a significant difference between the number of P.acutipennis in the all vegetation area (especially, Salix subfragilis) and the control area (no vegetation) during the investigation periods (P<0.05, Mann-Whitney U-test). Other taxa did not show a significant difference between the all vegetation area and the control. Moreover, the numbers of adult P. acutipennis showed a significant difference in height on each vegetation. In the case of Vicia villosa varia and V. villosa varia plus dead Phragmites australis, the highest number was caught in the traps set in the boundary between one plant and the plant above (P<0.05, Steel-Dwass Test) in May.On the other hand, in the case of almost all vegetation during the investigation periods (except of S.subfragilis in May, Melilotus officinalis plus dead P.australis in June), the highest number was caught in the traps set up within the vegetation (P<0.05, Steel-Dwass Test).As a result, a significant difference was observed in the number of trapped P.acutipennis according to the vegetation and its height.It is suggested that the existence of multiple types of vegetation in the floodplain plays an important role for maintaining the diversity of the fauna there.

Three-dimensional Simulation and Pattern Making of Collar Using Geometric Model

An algorithm is presented for computationally simulating collars and drafting patterns. The collar shape was modeled by three-dimensional Bezier patch. Changing the position of consol points of the patch can interactively control the collar shape. Using triangular surface developing method, patterns of various styles of stand collar and separating collar were drafted. As the subsystem of 3D apparel design system, an interactive collar design system is constructed. To inspect the practical usage, we reproduced the collars using these patterns drafted by the interactive collar design system.Comparing with simulated collars, the system demonstrated well and we found it is more reliable and accurate than the method of handwork.

Morphology and Microstructure of Spider Dragline Silk from Araneus Ventricosus

The spider dragline silk has excellent mechanical properties. The stress- strain curves of dragline silk fibers have intraspecific and intraindividual variability because of the spider’s active control during spinning process. To investigate the relationship between the morphology of dragline silk fibers and spinning conditions, four samples were made at the reeling rates of 1 mm/s, 20 mm/s, 43.5 mm/s and 110 mm/s from the major ampullate glands of Araneus Ventricosus and the other two of dragline silks were prepared from a crawling or dropping spider. The surface microstructure and nanofibril characteristic were analyzed with atomic force microscopy (AFM). AFM images of 2 000 nm *2 000 nm and 500 nm*500 nm of these samples showed that the spinning condition influenced the surface roughness and fibril size, while AFM images of 200 nm*200 nm clearly displayed that dragline silk of Araneus Ventricosus included sheet macro-conformation structure. These results can facilitate the further investigation of the spinning mechanism of a spider in order to understand mechanical properties and macromolecular structures of dragline silk.

Angle Control of a Pneumatically Driven Musculoskeletal Model Based on Coordination of Agonist-Antagonist Muscle

In recent years, researchers have been actively pursuing research into developing robots that can be useful in many fields of industry （e.g., service, medical, and aging care）. Such robots must be safe and flexible so that they can coexist with people. Pneumatic actuators are useful for achieving this goal because they are lightweight units with natural compliance. Our research focuses on joint angle control for a pneumatically driven musculoskeletal model. In such a model, we use a one-degree-of-freedom joint model and a five-fingered robot hand as test beds. These models are driven by low pressure-driven pneumatic actuators, and mimic the mechanism of the human hand and musculoskeletal structure, which has an antagonistic muscle pair for each joint. We demonstrated a biologically inspired control method using the parameters antagonistic muscle ratio and antagonistic muscle activity. The concept of the method is based on coordination of an antagonistic muscle pair using these parameters. We have investigated the validity of the proposed method both theoretically and experimentally, developed a feedback control system, and conducted joint angle control by implementing the test beds.

MXene-Based Photocatalysts and Electrocatalysts for CO_(2) Conversion to Chemicals

The interest in CO_(2)conversion to value-added chemicals and fuels has increased in recent years as part of strategic eff orts to mitigate and use the excessive CO_(2)concentration in the atmosphere.Much attention has been given to developing two-dimensional catalytic materials with high-effi ciency CO_(2)adsorption capability and conversion yield.While several candidates are being investigated,MXenes stand out as one of the most promising catalysts and co-catalysts for CO_(2)reduction,given their excellent surface functionalities,unique layered structures,high surface areas,rich active sites,and high chemical sta-bility.This review aims to highlight research progress and recent developments in the application of MXene-based catalysts for CO_(2)conversion to value-added chemicals,paying special attention to photoreduction and electroreduction.Furthermore,the underlying photocatalytic and electrocatalytic CO_(2)conversion mechanisms are discussed.Finally,we provide an outlook for future research in this fi eld,including photoelectrocatalysis and photothermal CO_(2)reduction.

ODOR DECOMPOSING FIBERS

1 Introduction Metallophthalocyanine(M-pc)have structures similar to active centerHemeenaymes such as oxidase,oxygenase,catalasse and peroxidase.We havestudied the synthesis of functional metallophthalocyanines and their polymersand their catalase-like as well as peroxidase activities as enzyme modeles 1)-

Seam Damage Control and Image Analysis for Cuprammonium Fabrics

Cuprammonium fabrics are susceptible to punctuation of the sewing needle during the manufacturing processes of a garment.This type of punctuation splits the yarns in the fabrics,creates ladder-like sewing defects,and seriously affects the aesthetics of the finished garment.To minimize this seam damage,a sandwiched structure of cuprammonium fabrics with a fusible interlining was proposed to enhance the friction between the yarns in the fabrics.A measurement system was set up to evaluate the seam damage,and the effects of stitch length and seam width on the seam damage were studied.The seam damage tended to become less severe as the stitch length increased.The addition of the fusible interlining between two pieces of the fabrics could effectively suppress the seam damage.The seam margin should be below or equal to 5 mm for the stitch length of 2.0 mm.An excessive seam margin might lead to a distorted seam.

Solvent Composition Effect on PDMS Composite Dielectric Elastomer Actuator

Polydimethylsiloxane (PDMS) is inactive to electric fields, but when combined with ferroelectric cyanoethyl sucrose (CR-U), it becomes an electrically active actuator material. The PDMS/CR-U composites were prepared by casting method using tetrahydrofuran (THF) and acetone (ACT) as solvents. The effect of a mixed solvent composition was investigated. The viscosity of the PDMS/CR-U/solvent solution decreased as the THF composition increased. The composite film obtained by evaporation of the solvent and cross-linkage of PDMS showed a phase-separated structure. Spherical CR-U dispersed in the PDMS matrix with a skin layer on one surface side. Electrical resistance, dielectric constant, space-charge distribution, and electrically induced bending deformation behavior were investigated for these composite films. The composite films prepared from a THF-rich solvent exhibited lower surface resistivity than those prepared from a THF-poor solvent. Applying an electric field to the composite film resulted in an asymmetric space-charge distribution with charge accumulation in the skin layer. THF content decreased the viscosity of the solution, meaning the decrease of the apparent size of PDMS chain aggregates. It allows the dispersion of CR-U in the PDMS matrix and also results in the decline of resistivity, the increase of permittivity, and the increase of charge injection. The results explained the structure formation of the composite film and the electric field response as an actuator. A casting solvent of THF content of 87.5 wt% or more is essential for the function of the PDMS/CR-U composite.

Pattern Recognition of Non-Stationary Time Series with Finite Length

Statistical learning and recognition methods were used to extract the characteristics of size series measurements of cocoon filaments that are non-stationary in terms of mean and auto-covariance, by using the time varying parameter auto-regressive （TVPAR） model. After the system was taught to recognize the size data, the system correctly recognized the size of series of cocoon filaments as much as 96.95% of the time for a single series and 98.72% of the time for the mean of two series. The correct recognition rate was higher after suitable filtering. The theory and method can be used to analyze other types of non-stationary finite length time series.

Physiological functions of hemocytes newly emerged from the cultured hematopoietic organs in the silkworm, Bombyx moil

Cellular immunity is a very important part of insect innate immunity. It is not clear if hemocytes entering the hemolymph require a maturation process to become competent. The establishment of a tissue culture system for the insect hematopoietic organs would enable physiological function assays with hemocytes newly emerged from hematopoietic organs. To this end, we established a hematopoietic organ culture system for the purebred silkworm pnd pS and then studied the physiological functions of the newly emerged hemocytes. We found that Grace＇s medium supplemented with 10% heated silkworm larval plasma was better for culturing the hematopoietic organs ofpndpS. Newly emerged hemocytes phagocytosed propidium iodide-labeled bacteria and encapsulated the Iml-2 coated nickel beads as well as pupal tissue debris. This culture system is therefore capable of generating physiologically functional hemocytes. These hemocytes can be used to study the mechanisms of the hemocyte immune response among others.

Deformable Textile‑Structured Triboelectric Nanogenerator Knitted with Multifunctional Sensing Fibers for Biomechanical Energy Harvesting

Fibers and textiles that harvest mechanical energy via the triboelectric effect are promising candidates as power supplies for wearable electronics.However,triboelectric fibers and textiles are often hindered by problems such as complex fabrication processes,limited length,performances below the state-of-the-art of 2D planar configurations,etc.Here,we demonstrated a scalable fabrication of core-sheath-structured elastomer triboelectric fibers that combine silicone hollow tubes with gelelectrodes.Gel-electrodes were fabricated via a facile freeze–thawing process of blending polyvinyl alcohol(PVA),gelatin,glycerin,poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)(PEDOT:PSS),and sodium chloride(NaCl).Such fibers can also be knitted into deformable triboelectric nanogenerator textiles with high electrical outputs up to 106 V and 0.8μA,which could work as reliable power supplies for small electronics.Moreover,we demonstrated fabric materials recognition,Morse code communication,and human-motion-recognition capabilities,making such triboelectric fiber platform an exciting avenue for multifunctional wearable systems and human–machine interaction.

A comparison of the pre-calling period between Japanese and southeastern Asian populations of Spodoptera litura

The pre-calling behavior of female adults of the common cutworm, Spodoptera litura （Lepidoptera： Noctuidae） collected in southern Japan and southeastern Asian countries was investigated. Most females started calling on days 1-4 after adult emergence. In three populations obtained in Saga prefecture in Kyushu mainland, Japan, two different patterns of pre-calling period （PCP） were observed： one was the above-mentioned pattern shown by most individuals, and the other was a pattern in which females sexually matured within several hours after emergence. Diel periodicity was shown in the time of calling activity, and its pattern varied among the populations. Pre-calling period was stable over successive generations in the laboratory.

Leaf-meridian bio-inspired nanofibrous electronics with uniform distributed microgrid and 3D multi-level structure for wearable applications

The interface between the active electronic and its osculatory target dominates the sensing response of high-sensitivity sensors.However,the interface properties are difficult to be adjusted and preserved owing to the limited strategies for surface engineering.In this work,inspired by nature frond leaf,a spatial multi-level nanofibrous membrane with grid-like microstructure of uniform distribution was fabricated,in which carboxylated carbon nanotubes(CCNTs)/poly(3,4-ethylenedioxythiophene)(PEDOT)was modified onto the surface of grid-like polyurethane(PU)nanofiber via the combination of metal mesh template,in situ polymerization and ultrasonic treatment.Nanofibrous membrane enables a pressure sensor with high sensitivities(5.13 kPa−1),fast response/recovery time(80 ms and 120 ms),and ultralow detection limit of 1 Pa.In addition,as a scalable and integrable platform,we also demonstrate its multifunctional applications for electro-thermal conversion and energy harvesting.All these results indicate the proposed nanofibrous membrane may potentially be applied to next-generation wearable devices.