Palladium diselenide (PdSe2), a thus far scarcely studied group‐10 transition metal dichalcogenide has exhibited promising potential in future optoelectronic and electronic devices due to unique ...structures and electrical properties. Here, the controllable synthesis of wafer‐scale and homogeneous 2D PdSe2 film is reported by a simple selenization approach. By choosing different thickness of precursor Pd layer, 2D PdSe2 with thickness of 1.2–20 nm can be readily synthesized. Interestingly, with the increase in thickness, obvious redshift in wavenumber is revealed by Raman spectroscopy. Moreover, in accordance with density functional theory (DFT) calculation, optical absorption and ultraviolet photoemission spectroscopy (UPS) analyses confirm that the PdSe2 exhibits an evolution from a semiconductor (monolayer) to semimetal (bulk). Further combination of the PdSe2 layer with Si leads to a highly sensitive, fast, and broadband photodetector with a high responsivity (300.2 mA W−1) and specific detectivity (≈1013 Jones). By decorating the device with black phosphorus quantum dots, the device performance can be further optimized. These results suggest the as‐selenized PdSe2 is a promising material for optoelectronic application.
This study reports on the wafer‐area synthesis of a high‐quality 2D palladium diselenide (PdSe2) layer through a simple selenization method. Both experimental analysis and theoretical simulation reveal that the PdSe2 film exhibits a gradual transition from a semiconductor (monolayer) to semimetal (bulk). Further combination of PdSe2 with Si leads to a fast and sensitive broadband photodiode, with a high responsivity and specific detectivity.
Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest malignant tumors of the human digestive system. Due to its insidious onset, many patients have already lost the opportunity for radical ...resection upon tumor diagnosis. In recent years, neoadjuvant treatment for patients with borderline resectable PDAC has been recommended by multiple guidelines to increase the resection rate of radical surgery and improve the postoperative survival. However, further developments are required to accurately assess the tumor response to neoadjuvant therapy and to select the population suitable for such treatment. Reductions in drug toxicity and the number of neoadjuvant cycles are also critical. At present, the clinical evaluation of neoadjuvant treatment is mainly based on several serological and imaging indicators; however, the unique characteristics of PDAC and the insufficient sensitivity and specificity of the markers render this system ineffective. The imaging evaluation system, magnetic resonance imaging (MRI), has its own unique imaging advantages compared with computed tomography (CT) and other imaging examinations. One key advantage is the ability to reflect the changes more rapidly in tumor tissue components, such as the degree of fibrosis, microvessel density, and tissue hypoxia. It can also perform multiparameter quantitative analysis of tumor tissue and changes, attributing to its increasingly important role in imaging evaluation, and potentially the evaluation of neoadjuvant treatment of pancreatic cancer, as several current articles have studied. At the same time, owing to the complexity of MRI and some of its limitations, its wider application is limited. Compared with CT imaging, few relevant studies have been conducted. In this review article, we will investigate and summarize the advantages, limitations, and future development of MRI in the evaluation of neoadjuvant treatment of PDAC.
Evidence Level
3
Technical Efficacy
Stage 2
Scintillators are widely utilized for radiation detections in many fields, such as nondestructive inspection, medical imaging, and space exploration. Lead halide perovskite scintillators have ...recently received extensive research attention owing to their tunable emission wavelength, low detection limit, and ease of fabrication. However, the low light yields toward X‐ray irradiation and the lead toxicity of these perovskites severely restricts their practical application. A novel lead‐free halide is presented, namely Rb2CuBr3, as a scintillator with exceptionally high light yield. Rb2CuBr3 exhibits a 1D crystal structure and enjoys strong carrier confinement and near‐unity photoluminescence quantum yield (98.6%) in violet emission. The high photoluminescence quantum yield combined with negligible self‐absorption from self‐trapped exciton emission and strong X‐ray absorption capability enables a record high light yield of ≈91056 photons per MeV among perovskite and relative scintillators. Overall, Rb2CuBr3 provides nontoxicity, high radioluminescence intensity, and good stability, thus laying good foundations for potential application in low‐dose radiography.
A new lead‐free halide Rb2CuBr3 scintillator with 1D crystal structure is presented. It exhibits self‐trapped exciton emission with a large Stokes shift (0.91 eV). Thus, it has near‐unity photoluminescence quantum yield (98.6%) and a high radioluminescence light yield of ≈91 056 photons per MeV.
A novel Mg-8Al-2Sn-1Zn alloy with a bimodal structure prepared by hard-pate-rolling (HPR) exhibits both higher tensile strength and ductility than its fine-grained counterparts prepared by ...conventional rolling. By delicate electron back-scatter diffraction (EBSD) analysis, we found fine grains with weak basal texture is beneficial for basal slip and favors initial deformation. Meanwhile, coarse grains with a strong basal texture could accommodate abundant newly generated dislocations, promoting work hardening after fine grains are saturated with dislocations. For the first time, individual roles of fine and coarse grains and their synergy effect on enhancing ductility in bimodal structured Mg alloys is clarified.
Display omitted
•A bimodal grain-structured Mg alloy is fabricated by hard-pate-rolling.•The bimodal sample has higher strength and ductility than fine-grained samples.•The synergy effect of fine and coarse grains on enhancing ductility is clarified.
Selective laser melting (SLM) is a powder bed layer-by-layer fusion technique mainly applied for additive manufacturing of 3D metallic components of complex geometry. However, the technology is ...currently limited to printing a single material across each layer. In many applications such as the manufacture of certain aero engine components, conformably cooled dies, medical implants and functional gradient structures, printing of multiple materials are desirable. This paper reports an investigation into the 3D printing of multiple metallic materials including 316L stainless steel, In718 nickel alloy and Cu10Sn copper alloy within a single build-up process using a specially designed multiple material SLM system combining powder-bed with point by point powder dispensing and selective material removal, for the first time. Material delivery system design, multiple material interactions, and component characteristics are described and the associated mechanisms are discussed.
Multidrug resistance （MDR） is a major hurdle in cancer chemotherapy and makes the treatment benefits unsustainable. Combination therapy is a commonly used method for overcoming MDR. In this study we ...investigated the anti-MDR effect of dihydroartemisinin （DHA）, a derivative of artemisinin, in combination with doxorubicin （Dox） in drug-resistant human colon tumor HCTS/ADR cells. We developed a tumor-targeting codelivery system, in which the two drugs were co-encapsulated into the mannosylated liposomes （Man- liposomes）. The Man-liposomes had a mean diameter of 158.8 nm and zeta potential of-15.8 mV. In the HCTS/ADR cells that overexpress the mannose receptors, the Man-liposomes altered the intracellular distribution of Dox, resulting in a high accumulation of Dox in the nuclei and thus displaying the highest cytotoxicity （ICso=0.073 pg/mL） among all the groups. In a subcutaneous HCT8/ADR tumor xenograft model, administration of the Man-liposomes resulted in a tumor inhibition rate of 88.59%, compared to that of 47.46% or 70.54%, respectively, for the treatment with free Dox or free Dox＋DHA. The mechanisms underlying the anti-MDR effect of the Man- liposomes involved preferential nuclear accumulation of the therapeutic agents, enhanced cancer cell apoptosis, downregulation of Bcl-xl, and the induction of autophagy.
Cadmium (Cd) accumulation in rice and its subsequent transfer to food chain is a major environmental issue worldwide. Understanding of Cd transport processes and its management aiming to reduce Cd ...uptake and accumulation in rice may help to improve rice growth and grain quality. Moreover, a thorough understanding of the factors influencing Cd accumulation will be helpful to derive efficient strategies to minimize Cd in rice. In this article, we reviewed Cd transport mechanisms in rice, the factors affecting Cd uptake (including physicochemical characters of soil and ecophysiological features of rice) and discussed efficient measures to immobilize Cd in soil and reduce Cd uptake by rice (including agronomic practices, bioremediation and molecular biology techniques). These findings will contribute to ensuring food safety, and reducing Cd risk on human beings.
Display omitted
•Radial oxygen loss controls Fe plaque formation on rice roots and affects Cd uptake.•Flooding before and after heading is effective for reducing Cd uptake by rice.•Inoculation with suitable AMF can be applied to reduce Cd accumulation in rice.•Intercropping and rotation systems can decrease Cd uptake by rice.
Cd transport mechanisms, factors influencing Cd accumulation, and efficient strategies to reduce Cd uptake by rice are summarized.
Electronic skins have received substantial attention in recent years and found great potential in prosthetics, robots, wearable devices, medical equipment, and many other areas. The development of ...the emerging field of nanogenerators and piezotronics unveiled new types of flexible electronic skins. These devices demonstrated high sensitivity, rapid response, and self-power capability. This review gives the research progress of electronic skins based on principles found in nanogenerators and piezotronics. The role of the piezoelectric effect and the piezotronic effect in sensors is explored, materials used in devices are discussed, and different sensors for electronic skins are provided in this review. The review concludes with an outlook of electronic skins enabled by nanogenerators and piezotronics.
Display omitted
The economic amino-modified covalent triazine frameworks with good porosity and stability for meeting the gold adsorption requirements have been designed and synthesized for gold recovery from waste ...electronic and electric equipment.
Display omitted
•The amino-functionalized covalent triazine frameworks (NH2-CTFs) were prepared for gold recovery from waste electronic and electric equipment.•NH2-CTFs with high porosity and good thermal stability exhibit excellent gold recovery performance.•The gold ions can be in situ reduced into gold nanoparticles by NH2-CTFs and the purity of recovered gold is up to 23.4 karat.•NH2-CTF-1 possesses high gold uptake capacity and outstanding gold recovery profit.
Recycling gold from e-waste is not only conducive to alleviating the pressure on resources and environment, but also has high economic value. Therefore, construction of adsorbents with high capacity and selectivity and low cost is significative for gold recovery from waste electronic and electric equipment (WEEE). Herein, amino-functionalized covalent triazine frameworks (NH2-CTFs) were synthesized by ionothermal conditions. NH2-CTF-1 and NH2-CTF-2 with high porosity and good thermal stability exhibit excellent gold recovery performance. Meanwhile, gold ions can be in situ reduced into gold nanoparticles by NH2-CTFs along with the adsorption process. Furthermore, NH2-CTF-1 and NH2-CTF-2 present good gold adsorption selectivity from WEEE. Notably, NH2-CTF-1 possesses high gold adsorption capacity (909 mg g−1) and outstanding recovery profit. These excellent performances confirm the potential of NH2-CTF-1 and NH2-CTF-2 for gold recovery from WEEE.
PDF
