Microstructures and mechanical properties of a commercial Mg-Al-Zn-Mn alloy with various hot-extrusion processes

Mg-Al-Zn-Mn(AZ)system alloys have become widely used due to their good castability,excellent formability and outstanding corrosion resistance[1-6].However,their strength is still much lower than that of traditional Mg-RE(rare earth)based alloys or even some new Mg-Li basedalloys[7-19].

Clinical factors associated with the number of gallbladder polyps

Gallbladder polyps(GBPs),which are defined as a pathological change protruding from the gallbladder mucosa,are one of the main causes of hospital admission for cholecystectomy.The incidence of GBPs is 4.2 to 9.5%in China.To date,the etiology of GBPs has not yet been clearly defined.According to previous studies,metabolic status is strongly associated with GBPs.⑵A single polyp is more likely to exhibit a malignant transformation,and large(diameter greater than 10 mm)single polyps should be resected together with the entire gallbladder.However,multiple polyps seem unlikely to transform.Thus,number of GBPs is an important factor that affects the treatment of GBPs.However,clinical factors associated w让h the number of GBPs are not completely understood;therefore,the aim of the current study is to investigate these factors.

Detailed Structures and Formation Mechanisms of Well-Known Al_(10)RE_2Mn_7 Phase in Die-Cast Mg-4Al-4RE-0.3Mn Alloy

The detailed structures and the corresponding formation mechanisms of the well-known Al_(10)RE_2Mn_7 phase in the conventional die-cast Mg–4Al–4RE–0.3Mn alloy were thoroughly investigated using transmission electron microscopy(TEM). The results indicate that the Al_(10)RE_2Mn_7 phase ordinarily contains both normal (111) twins and orientation twins.Both detailed TEM observations and density functional theory calculations indicate that the Al_(10)RE_2Mn_7 phase is transferred from the Al_8REMn_4 phase following an orientation relationship as [010]_(Al_8REMn_4)//[101]_(Al_(10)RE_2Mn_7) and (101)_(Al_8REMn_4)//(110)_(Al_(10)RE_2Mn_7). Moreover, forming orientation twins in the Al_(10)RE_2Mn_7 phase is attributed to the blurry regions at incoherent twin boundaries in the Al_8REMn_4 phase. Finally, these formed orientation twins result in the (111) twins in the Al_(10)RE_2Mn_7 phase.

β-CuGaO_(2):a ferroelectric semiconductor with narrow band gap as degradation catalyst for wastewater environmental remediation

As a narrow band gap semiconductor,wurtziteβ-CuGaO_(2)has drawn increasing attention in the area of solar energy.Althoughβ-CuGaO_(2)has been theoretically predicted to possess ferroelectric polarization,its experi-mental ferroelectric characterization and practical appli-cations have not yet been presented.Herein,firstly we experimentally confirmed its ferroelectric property via hysteresis loop measurement.The result showed a rema-nent polarization value of 10.20μC·cm^(-2) with low coer-cive electricfield of 6.45 kV·cm^(-1) at 20 Hz at room temperature,while the leakage current density(J)value was found to be 1.188 A·cm^(-2),which suggested the property of a larger remnant polarization with low coercive electricfield than current value if the compactness was strengthened.Then,the synergistic effect of ferroelectric and semiconductor was comparatively highlighted by the experiment of pollutant degradation.Within 30 min,methyl orange degradation efficiency had reached 30.73%only in the case of spontaneous polarization(electricity),while it could reach 67.58%under the effect of pre-po-larizedβ-CuGaO_(2)powder due to the modulating orienta-tion of ferroelectric domains.Once irradiated(light),it was up to 92%within 30 min;in comparison,it merely took 16 min up to 92%degradation efficiency under both illu-mination and pre-polarization.If without illumination,it was 92.01%with 30 min in the condition of ordinary ultrasonic vibration(force)while under both illumination and ultrasonic vibration,only 11 min was spent to reach 92.79%degradation efficiency.All these results felici-tously indicated thatβ-CuGaO_(2)had fascinating potential in energy harvesting(such as electricity,light,force)and transformation as wastewater environment remediation catalyst.

Synthesis and Properties of SEPS-g-PEO Copolymers with Varying Branch Lengths

Poly（ethylene oxide） （PEO） was controllably grafted from styrene-b-（ethylene-co-propylene）-b-styrene （SEPS） backbones by combining lithiation of styrenic units and living monomer-activated anionic ring-opening polymerization of ethylene oxide （EO） monomers with the aid of co-initiators triisobutyl aluminum. The as-synthesized SEPS-g-PEO copolymers were characterized by SEC, 1H-NMR, FTIR, SAXS, AFM and DSC. When the branch length is relatively small, increase of PEO fraction leads to the increase of the correlation length between neighboring hard domains, but the degree of correlation reduces. When the branch length is relatively large, the phase-separated structures become random both in terms of size and spatial correlation, and macro-phase separated structures appear. The crystallization behavior of the PEO branches can be effectively inhibited in SEPS-g-PEO, so no significant crystallization takes place until the fraction of PEO branches is 20.1 wt%, which greatly promotes the rapid delivery of hydrophilic drugs in the hot-melting pressure- sensitive adhesives （HMPSAs） based on SEPS-g-PEO. Their cumulative release amount of a model drug could achieve 80%, more than twice the value in the HMPSAs based on linear PEO-containing styrenic block copolymers.