Electric vehicles using lithium-ion battery pack(s) for propulsion have recently attracted a great deal of interest. The large-scale practical application of battery electric vehicles may not be ...realized unless lithium-ion batteries with self-charging suppliers will be developed. Solar cells offer an attractive option for directly photo-charging lithium-ion batteries. Here we demonstrate the use of perovskite solar cell packs with four single CH3NH3PbI3 based solar cells connected in series for directly photo-charging lithium-ion batteries assembled with a LiFePO4 cathode and a Li4Ti5O12 anode. Our device shows a high overall photo-electric conversion and storage efficiency of 7.80% and excellent cycling stability, which outperforms other reported lithium-ion batteries, lithium-air batteries, flow batteries and super-capacitors integrated with a photo-charging component. The newly developed self-chargeable units based on integrated perovskite solar cells and lithium-ion batteries hold promise for various potential applications.
The compliance of soft grippers contributes to their great superiority over rigid grippers in grasping irregularly shaped objects and forming soft contact with environments. Due to a relatively small ...pressure, soft grippers lack the stiffness required for wider applications. Particle jamming has been frequently reported as a means of stiffness control. Unlike previous research using vacuum for particle jamming, this paper proposes a novel passive particle jamming principle that does not need any vacuum power or other control means. The proposed method is by simply patching a silicone rubber soft actuator and a pack (made of strain-limiting membrane) of particles to form an integral gripping finger. The inflation of the soft actuator applies a pressure to the particle pack causing particles inside it to jam. A larger squeezing pressure will result in tighter particle jamming, thus increasing the stiffness of the finger. The stiffness of the finger is controllable as it is proportional to the actuator's air pressure, which has been verified by experiments in this research. The stiffness can increase more than six fold when air pressure changes from 20 to 80 kPa in the experimental studies. The reported discovery may enhance the capabilities of soft robotic grippers so that more robotic picking operations could be performed by soft grippers.
Circular RNAs (circRNAs) are recently discovered new endogenous non-coding RNAs and an area of much research activity. In addition to their potential as major gene regulators, reports are linking ...heterogeneous circRNA groups with many different human disorders, especially cancer. In this review, we focus on the rapidly advancing field of circRNAs that play a part in human diseases. We list tools (eg, public databases) that scan genome spans of interest to identify known circRNAs; describe the relationship between dysregulated circRNAs and human disease, highlighting their specific roles; and consider the possible use of current and potential circRNA research applications in treating human diseases. Specifically, we review the role of circRNAs as biomarkers, drug targets and therapeutic agents.
A layer‐by‐layer approach is developed to prepare uniform and compact CH3NH3PbI3−xClx perovskite films for perovskite solar cells with a high efficiency up to 15.12% and an improved stability. ...Moreover, a record high efficiency of 12.25% is achieved for these flexible perovskite solar cells. This study represents an important step forward in developing high‐performance and stable perovskite solar cells.
In recent years, organometal trihalide perovskites have emerged as promising materials for low‐cost, flexible, and highly efficient solar cells. Despite their processing advantages, before the ...technology can be commercialized the poor stability of the organic–inorganic hybrid perovskite materials with regard to humidity, heat, light, and oxygen has be to overcome. Herein, we distill the current state‐of‐the‐art and highlight recent advances in improving the chemical stability of perovskite materials by substitution of the A‐cation and X‐anion. Our hope is to pave the way for the rational design of perovskite materials to realize perovskite solar cells with unprecedented improvement in stability.
Stability rising: The recent advances in improving the chemical stability of perovskite materials in terms of substitution of A‐cation and X‐anion are reviewed. The aim is to open new perspectives for the rational design of perovskite materials to create perovskite solar cells with unprecedented stability for outdoor applications.
Early studies on robot machining were reported in the 1990s. Even though there are continuous worldwide researches on robot machining ever since, the potential of robot applications in machining has ...yet to be realized. In this paper, the authors will first look into recent development of robot machining. Such development can be roughly categorized into researches on robot machining system development, robot machining path planning, vibration/chatter analysis including path tracking and compensation, dynamic, or stiffness modeling. These researches will obviously improve the accuracy and efficiency of robot machining and provide useful references for developing robot machining systems for tasks once thought to only be capable by CNC machines. In order to advance the technology of robot machining to the next level so that more practical and competitive systems could be developed, the authors suggest that future researches on robot machining should also focus on robot machining efficiency analysis, stiffness map-based path planning, robotic arm link optimization, planning, and scheduling for a line of machining robots.
This article presents a novel method of shape memory polymer (SMP) processing for additive manufacturing, in particular, fused-deposition modeling (FDM). Critical extrusion process parameters have ...been experimented to determine an appropriate set of parameter values so that good-quality SMP filament could be made for FDM. In the FDM process, effects of different printing parameters such as extruder temperature and scanning speed on object printing quality are also studied. In all the process studies, we aim to achieve good-quality parts by evaluating part density, tensile strength, dimensional accuracy, and surface roughness. Based on these studies, sample SMP models have been successfully built. Due to the thermal sensitive nature of the printed SMP parts, they can potentially be used as fasteners in active assembly/disassembly, smart actuators, deployable structures for aero-space applications, etc.
While halide perovskites (HPs) have achieved enormous success in the field of optoelectronic applications, much attention has been recently drawn to the unique polarization sensitivity of HPs, either ...intrinsic or extrinsic, which makes HPs a potential candidate for innovative applications in directly polarized luminescence and detection. Herein, the research status in the field of polarization‐sensitive HPs, including linear polarization and circular polarization, is comprehensively summarized. To evaluate the effectiveness of HPs in generating and detecting linearly or circularly polarized light, the principles and characterization methods of polarized luminescence and detection are introduced. Sequentially, the state‐of‐the‐art development of the strategies that induce the linear or circular polarization characteristics of HPs is systematically reviewed, based on which the application of polarization‐sensitive HPs in the field of polarization luminescence and detection are summarized. Moreover, the current challenges and opportunities are discussed, and prospects of the future development in this promising field are outlined.
The current developments and advanced understanding of polarization‐sensitive halide perovskites are comprehensively reviewed, involving linear/circular polarization luminescence and detection. Also, the key challenges and current opportunities in the field are discussed. The great promise of polarization‐sensitive halide perovskites is addressed to inspire other potential applications in opotoelectronics.
Organic–inorganic hybrid halide perovskites (e.g., MAPbI3) have recently emerged as novel active materials for photovoltaic applications with power conversion efficiency over 22%. Conventional ...perovskite solar cells (PSCs); however, suffer the issue that lead is toxic to the environment and organisms for a long time and is hard to excrete from the body. Therefore, it is imperative to find environmentally‐friendly metal ions to replace lead for the further development of PSCs. Previous work has demonstrated that Sn, Ge, Cu, Bi, and Sb ions could be used as alternative ions in perovskite configurations to form a new environmentally‐friendly lead‐free perovskite structure. Here, we review recent progress on lead‐free PSCs in terms of the theoretical insight and experimental explorations of the crystal structure of lead‐free perovskite, thin film deposition, and device performance. We also discuss the importance of obtaining further understanding of the fundamental properties of lead‐free hybrid perovskites, especially those related to photophysics.
Recent progress on lead‐free perovskite solar cells (PSCs) in terms of the theoretical insight and experimental explorations of the crystal structure of lead‐free perovskites, thin‐film deposition, and device performance is reviewed. The importance of understanding the fundamental properties of lead‐free hybrid perovskites is discussed. Greater effort is needed to explore high‐performance lead‐free PSCs.
Overwhelming evidence demonstrates that exosomes, a series of biologically functional small vesicles of endocytic origin carrying a variety of active constituents, especially tumor‐derived exosomes, ...contribute to tumor progression and metastasis. This review focuses on the specific multifaceted roles of exosomes in affecting sequenced four crucial processes of metastasis, through which cancer cells spread from primary to secondary organs and finally form macroscopic metastatic lesions. First, exosomes modulate the primary tumor sites to assist cancer growth and dissemination. In this part, five main biological events are reviewed, including the transfer of oncogenic constituents, the recruitment and activation of fibroblasts, the induction of angiogenesis, immunosuppression and epithelial‐mesenchymal transition (EMT) promotion. In Step 2, we list two recently disclosed mechanisms during the organ‐specific homing process: the exosomal integrin model and exosomal epidermal growth factor receptor (EGFR)/miR‐26/hepatocyte growth factor (HGF) model. Subsequently, Step 3 focuses on the interactions between exosomes and pre‐metastatic niche, in which we highlight the specific functions of exosomes in angiogenesis, lymphangiogenesis, immune modulation and metabolic, epigenetic and stromal reprogramming of pre‐metastatic niche. Finally, we summarize the mechanisms of exosomes in helping the metastatic circulating tumor cells escape from immunologic surveillance, survive in the blood circulation and proliferate in host organs.
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