Self-Healing Liquid Metal Magnetic Hydrogels for Smart Feedback Sensors and High-Performance Electromagnetic Shielding

Hydrogels exhibit potential applications in smart wearable devices because of their exceptional sensitivity to various external stimuli.However,their applications are limited by challenges in terms of issues in biocompatibility,custom shape,and self-healing.Herein,a conductive,stretchable,adaptable,self-healing,and biocompatible liquid metal GaInSn/Ni-based composite hydrogel is developed by incorporating a magnetic liquid metal into the hydrogel framework through crosslinking polyvinyl alcohol(PVA)with sodium tetraborate.The excellent stretchability and fast self-healing capability of the PVA/liquid metal hydrogel are derived from its abundant hydrogen binding sites and liquid metal fusion.Significantly,owing to the magnetic constituent,the PVA/liquid metal hydrogel can be guided remotely using an external magnetic field to a specific position to repair the broken wires with no need for manual operation.The composite hydrogel also exhibits sensitive deformation responses and can be used as a strain sensor to monitor various body motions.Additionally,the multifunctional hydrogel displays absorption-dominated electromagnetic interference(EMI)shielding properties.The total shielding performance of the composite hydrogel increases to~62.5 dB from~31.8 dB of the pure PVA hydrogel at the thickness of 3.0 mm.The proposed bioinspired multifunctional magnetic hydrogel demonstrates substantial application potential in the field of intelligent wearable devices.

In-situ grown Ni Co bimetal anchored on porous straw-derived biochar composites with boosted microwave absorption properties

With the gradually increasing protection awareness about electromagnetic pollution,the demand for absorbing materials with renewability and environmental friendliness has attracted widespread attention.In this work,composites consisting of straw-derived biochar combined with NiCo alloy were successfully fabricated through high-temperature carbonization and subsequent hydrothermal reaction.The electromagnetic parameters of the porous biocarbon/NiCo composites can be effectively modified by altering their NiCo content,and their improved absorbing performance can be attributed to the synergy effect of magnetic-dielectric characteristics.An exceptional reflection loss of-27.0 dB at 2.2 mm thickness and an effective absorption bandwidth of 4.4 GHz(11.7-16.1 GHz)were achieved.These results revealed that the porous biocarbon/NiCo composites could be used as a new generation absorbing material because of their low density,light weight,excellent conductivity,and strong absorption.

Development and Practice of Integrated Nursing Model NNN Link for Breastfeeding Clinical Nursing Model as a Whole

Objective: To establish breastfeeding clinical holistic nursing model used in clinical nursing and teaching, it is possible to improve nurses and nursing students to master knowledge of breastfeeding, analysis, judgment, decision-making and the ability to care-related issues, promoting pure improve breastfeeding rates. Method: 1) The North American Nursing Diagnosis Nursing Association (NANDA), Nursing Outcomes Classification (NOC) and Nursing Classification (NIC) link (NNN link) clinical clues reasoning to determine the contents of the questionnaire were used. Then, the Delphi method to care was used. 2) The survey questionnaire was designed. The content included the clinical holistic nursing care model in breastfeeding and the model’s use situation. 3) Questionnaire survey: in the national midwifery care industries, volunteers were collected who were willing to use the breastfeeding clinical holistic nursing care model in the nursing work. We issued 98 questionnaires and took back 76 valid questionnaires. Results: The construction of the breastfeeding clinical holistic nursing model includes 9 nursing diagnoses which contain the breastfeeding effective, the lack of knowledge, the decision conflicts, the risk of breast tenderness, the risk of cracked nipple, the invalid hazard occurring in breastfeeding, the risk of caregiver role strain, the risk of breast feeding jaundice and the ineffective community coping, 18 nursing outcomes and 64 nursing measures. In the composition of breastfeeding after clinical holistic nursing model in clinical practice, 100% of obstetric nurses think that the breastfeeding nursing model can promote the nursing staff to care patients according to the nursing process, can help nurses to analyze, evaluate, make decision, and care about breastfeeding related problems, as well as can promote the mother’s milk feeding rate. Conclusion: The establishment of the breastfeeding nursing model provides a learning material for obstetric breast-feeding. Moreover, nursing diagnosis, nursing outcomes and nursing measures correspond according to the form of chart, which are easy to use and find. The breastfeeding clinical holistic nursing model is practicing in clinical nursing, which can help nursing staff to improve the ability of nursing personnel according to evidence-based nursing patients, to improve the ability of nursing personnel analysis, evaluation, decision-making and nursing in breastfeeding problems and to promote the rate of breastfeeding.

不同类型止血材料在创伤急救中的应用研究进展

止血材料对于战场和灾难环境中大量失血创伤患者的救治至关重要。针对受伤部位和受伤严重程度不同, 需要使用不同类型的止血材料来紧急止血。目前对于体表伤口、四肢及交界处出血, 急救止血材料已得到很好的应用, 而针对胸腹腔及腔内脏器等出血创口较深且不可压迫性出血情况, 在急救早期处理中仍无理想的止血材料。笔者就现有止血材料的分类和作用机制, 以及在创伤急救中的应用与研究进展进行综述, 为创伤出血急救早期止血材料的应用提供参考。

Facile synthesis of yolk-shell Ni@void@SnO2（Ni3Sn2） ternary composites via galvanic replacement/Kirkendall effect and their enhanced microwave absorption properties

Yolk-shell ternary composites composed of a Ni sphere core and a SnO2（Ni3Sn2） shell were successfully prepared by a facile two-step method. The size, morphology, microstructure, and phase purity of the resulting composites were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy （TEM）, high-resolution TEM, selected-area electron diffraction, and powder X-ray diffraction. The core sizes, interstitial void volumes, and constituents of the yolk-shell structures varied by varying the reaction time. A mechanism based on the time-dependent experiments was proposed for the formation of the yolk-shell structures. The yolk-shell structures were formed by a synergistic combination of an etching reaction, a galvanic replacement reaction, and the Kirkendall effect. The yolk-shell ternary SnO2 （Ni3Sn2）@Ni composites synthesized at a reaction time of 15 h showed excellent microwave absorption properties. The reflection loss was found to be as low as -43 dB at 6.1 GHz. The enhanced microwave absorption properties may be attributed to the good impedance match, multiple reflections, the scattering owing to the voids between the core and the shell, and the effective complementarities between the dielectric loss and the magnetic loss. Thus, the yolk-shell ternary composites are expected to be promising candidates for microwave absorption applications, lithium ion batteries, and photocatalysis.

Structure-dependent electromagnetic wave absorbing properties of bowl-like and honeycomb TiO_(2)/CNT composites

Materials that can efficiently absorb electromagnetic waves(EMWs)are required to deal with electromagnetic pollution.Structure design appears to be an efficient way to improve the EMW-absorption performance of such materials,particularly when adjustment of the constitution or mixing ratio is limited.In this study,bowl-like and honeycomb titanium dioxide/carbon nanotube(TiO_(2)/CNT)composites with different CNT contents were fabricated using the methods of hierarchical and mixing vacuum-assisted filtration,respectively.Compared to the honeycomb structure,the bowl-like structure simultaneously facilitated greater interfacial polarization and conduction loss in favor of dielectric polarization,and augmented multiple reflections.The high porosity of the honeycomb structure was conducive to optimizing the impedance matching characteristics.The bowl-like TiO_(2)/CNT composite exhibited a minimum reflection loss(RL_(min))of-38.6 dB(1.5 mm)with a wide effective absorption band(EAB;<-10 dB)of4.2 GHz,while the honeycomb TiO_(2)/CNT composite showed an RLminof-34.8 dB(2.1 mm)with an EAB of 4.3 GHz.The required mixing ratio in the matrix was only 15 wt%,outperforming that of the most closely related composites.Thus,both the bowl-like and honeycomb TiO_(2)/CNT composites are ideal candidates for light-weight and highly efficient EMW-absorbing materials.

Dependence of electromagnetic wave absorption properties on the topography of Ni anchoring on reduced graphene oxide

Specific topographic Ni anchoring on reduced graphene oxide(rGO) composites show an astronomical potential as effective wave absorbers due to the synergistic electromagnetic loss effects.Herein,Ni/rGO composites with different topography were successfully prepared via hydrothermal in-situ reduction method.The structure and morphology characteristics revealed that particle-like,chain-like,coin-like and flower-like Ni were closely anchored onto rGO,respectively.The electromagnetic wave absorption(EMA) performance revealed that chain-like Ni/rGO exhibited the optimal reflection loss of-43.7 dB with a thickness of 1.8 mm as well as the EAB of 6.1 GHz at 2.0 mm among all samples due to the good impedance match and the synergistic dielectric and magnetic losses.Besides,one conclusion can be drawn that excellent magnetic coupling effect and impedance matching were the main reasons for significantly improving the EMA performance.Considering the systematic dependence of morphology on EMA,this work provides a perspective for designing high-performance absorbing materials.