Radiation graft of acrylamide onto polyethylene separators for lithium-ion batteries

To improve the affinity between separators and electrolyte in lithium-ion battery,microporous polyethylene(PE) separator was grafted of polyacrylamide(PAAm) by radiation.Chemical structure of the PAAmgrafted PE separators(denoted as PE-g-PAAm) was characterized by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy.Properties of the pristine PE and PE-g-PAAm were tested by scanning electron microscope,liquid electrolyte uptake and lithium-ion conductivity.Electrochemical performances of the grafted PE separators(up to 0.76 × 10^(-3) S/cm of ionic conductivity at room temperature) were much better than pristine PE,and performance of the battery with the grafted separator behaved better than with the virgin PE separator,under the same condition(assembled in Ar-filled glove box).

Radiation-induced cross-linking:a novel avenue to permanent 3D modification of polymeric membranes

Membrane fouling is always the biggest problem in the practice of membrane separation technologies,which strongly impacts their applicability,separation efficiency,cost effectiveness,and service lifespan.Herein,a simple but effective 3D modification approach was designed for permanently functionalizing polymeric membranes by directly cross-linking polyvinyl alcohol(PVA)under gamma-ray irradiation at room temperature without any additives.After the modification,a PVA layer was constructed on the membrane surface and the pore inner surface of polyvinylidene fluoride(PVDF)membranes.This endowed them with good hydrophilicity,low adsorption of protein model foulants,and easy recoverability properties.In addition,the pore size and distribution were customized by controlling the PVA concentration,which enhanced the rejection ability of the resultant membranes and converted them from microfiltration to ultrafiltration.The crosslinked PVA layer was equipped with the resultant membranes with good resistance to chemical cleaning by acidic,alkaline,and oxidative reagents,which could greatly prolong the membrane service lifetime.Furthermore,this approach was demonstrated as a universal method to modify PVDF membranes with other hydrophilic macromolecular modifiers,including polyethylene glycol,sodium alginate,and polyvinyl pyrrolidone.This modification of the membranes effectively endowed them with good hydrophilicity and antifouling properties,as expected.

Simple synthesis of silver nanocluster composites AgNCs@PE-g-PAA by irradiation method and fluorescence detection of Cr^(3+)

Silver nanoclusters(AgNCs)are a new type of nanomaterials with similar properties to molecules and unique applications.The applications of AgNCs can be significantly expanded by combining them with different matrix materials to obtain AgNC composites.Using irradiation techniques,we developed a simple two-step method for preparing silver nanocluster composites.First,polyacrylic acid(PAA)chains were grafted onto the surface of a PE film as templates(PE-g-PAA).Subsequently,silver ions were reduced in situ on the surface of the template material to obtain the AgNC composites(AgNCs@PE-g-PAA).The degree of AgNC loading on the composite film was easily controlled by adjusting the reaction conditions.The loaded AgNCs were anchored to the carboxyl groups of the PAA and wrapped in the graft chain.The particle size of the AgNCs was only 4.38±0.85 nm,with a very uniform particle size distribution.The AgNCs@PE-g-PAA exhibited fluorescence characteristics derived from the AgNCs.The fluorescence of the AgNCs@PE-g-PAA was easily quenched by Cr^(3+)ions.The composite can be used as a fluorescence test paper to realize visual detection of Cr^(3+).

Preparation of antibacterial non-woven AgNCs@PP-g-PAA via radiation method

With the growing threat of airborne epidemics,there has been an increasing emphasis on personal protection.Masks serve as our primary external defense against bacteria and viruses that might enter the respiratory tract.Hence,it’s crucial to develop a polypropylene(PP)nonwoven fabric with quick antibacterial capabilities as a key component for masks.This study introduces silver nanoclusters(AgNCs)into non-woven PP using radiation technology to infuse antibacterial properties.Initially,a solid ligand(PP-g-PAA)was procured via radiation grafting of the ligand polyacrylic acid(PAA),which was incorporated into the nonwoven PP with the aid of a crosslinking agent at a lower absorbed dosage.Subsequently,AgNCs were synthesized in situ on PP-g-PAA via an interaction between PAA and AgNCs,leading directly to the formation of AgNCs@PP-g-PAA composites.Owing to the hydrophilicity of PAA,AgNCs@PP-g-PAA maintains good moisture permeability even when the voids are heavily saturated with PAA gel,preventing droplet aggregation by diffusing droplets on the surface of the material.This feature enhances the comfort of the masks.Most importantly,due to the incorporation of AgNCs,AgNCs@PP-g-PAA demonstrates outstanding antibacterial effects against Escherichia coli and Staphylococcus aureus,nearly achieving an instant“touch and kill”outcome.In conclusion,we synthesized a modified nonwoven fabric with significant antibacterial activity using a simple synthetic route,offering a promising material that provides improved personal protection.

Research on the origin of the theory of“heart as monarch”in Huang Di Nei Jing(Yellow Emperor’s Internal Classic)

Scholars have previously attributed the theoretical origin of“the heart is the monarch/ruler”to the monarchical view of politics.However,according to the latest unearthed documents and relevant documents handed down from ancient times,it can be found that the theory of“the heart is the monarch”might derive from the importance of attachment to the“Zhong”ideology in traditional culture,which promoted the concept that the heart as the center of body,should be the ruler and was later evolved as the“monarch”.Similar cognitive views were all mentioned in Confucianism,Taoism,eclectics scholars and other pre-Qin literature,but only in the system of traditional Chinese medicine,they played a significant role in building the heart-centered theory of Zang-Fu.Traditional Chinese medicine is a discipline developed mainly by clinical practice with the fundamental purpose of curing diseases and saving people.Although the philosophy of traditional Chinese medicine(TCM)roots in the pre-Qin Dynasty,the development is unique to the other philosophies.With rich cultural connotations and philosophical thoughts,TCM is certainly the key to the treasures of Chinese civilization and deserves more attention and exploration.

The synergy reduction and self-assembly of graphene oxide via gamma-ray irradiation in an ethanediamine aqueous solution

Gamma-ray irradiation technique is an effective method for preparing graphene aerogel(GA).The effective reduction and self-assembly of graphene oxide(GO) sheets into 3D porous GA in ethylenediamine(EDA) aqueous solution under the protection of nitrogen have been achieved via γ-ray irradiation.The reduction degree and self-assembly process,which can be controlled by varying EDA dose and irradiation dose,are investigated by X-ray photoelectron spectroscopy,Fourier transform infrared spectroscopy,X-ray diffractometer,and thermogravimetric analysis.A reduction mechanism is proposed for interactions among EDA molecules,active radicals from the radiolysis of water,and oxygen-containing groups on GO sheets.