A Personal Desktop Liquid-Metal Printer as a Pervasive Electronics Manufacturing Tool for Society in the Near Future

It has long been a dream in the electronics industry to be able to write out electronics directly, as simply as printing a picture onto paper with an offi ce printer. The fi rstever prototype of a liquid-metal printer has been invented and demonstrated by our lab, bringing this goal a key step closer. As part of a continuous endeavor, this work is dedicated to significantly extending such technology to the consumer level by making a very practical desktop liquid-metal printer for society in the near future. Through the industrial design and technical optimization of a series of key technical issues such as working reliability, printing resolution, automatic control, human-machine interface design, software, hardware, and integration between software and hardware, a high-quality personal desktop liquid-metal printer that is ready for mass production in industry was fabricated. Its basic features and important technical mechanisms are explained in this paper, along with demonstrations of several possible consumer end-uses for making functional devices such as li ght-emitting diode(LED) displays. This liquid-metal printer is an automatic, easyto-use, and low-cost personal electronics manufacturing tool with many possible applications. This paper discusses important roles that the new machine may play for a group of emerging needs. The prospective future of this cuttingedge technology is outlined, along with a comparative interpretation of several historical printing methods. This desktop liquid-metal printer is expected to become a basic electronics manufacturing tool for a wide variety of emerging practices in the academic realm, in industry, and in education as well as for individual end-users in the near future.

A Computational Study on the Effect of Bifurcation Lesions with DifferentStructures on Blood Velocity and Temperature

Treating coronary bifurcation stenosis is still a challenging task. Existing procedures still display a relatively smallrate of success. This paper aims to investigate numerically the effect of bifurcation lesions with different structureson the dynamics of blood flow and related temperature. The problem geometry is parametrically varied by changing the bifurcation angle and radius. A finite volume method is used to simulate the three-dimensional flow. Theeffects induced by the structure of the stenosis, the artery bifurcation angle and radius, and the inlet velocity ofblood are discussed in terms of flow pattern, pressure distribution, and shear stress at the blood wall. The heattransfer from the solid tissue is also determined for different stenosis configurations. The present study has beenconducted with the explicit intention to generate useful data for the development of methods curing the vascularstenosis with thermal ablation.

High heat flux thermal management through liquid metal driven with electromagnetic induction pump

In this paper, a novel liquid metal-based minichannel heat dissipation method was developed for cooling electric devices with high heat flux. A high-performance electromagnetic induction pump driven by rotating permanent magnets is designed to achieve a pressure head of 160 kPa and a flow rate of 3.24 L/min, which could enable the liquid metal to remove the waste heat quickly. The liquid metal-based minichannel thermal management system was established and tested experimentally to investigate the pumping capacity and cooling performance. The results show that the liquid metal cooling system can dissipate heat flux up to 242 W/cm2 with keeping the temperature rise of the heat source below 50°C. It could remarkably enhance the cooling performance by increasing the rotating speed of permanent magnets. Moreover, thermal contact resistance has a critical importance for the heat dissipation capacity. The liquid metal thermal grease is introduced to efficiently reduce the thermal contact resistance (a decrease of about 7.77 × 10−3 °C/W). This paper provides a powerful cooling strategy for thermal management of electric devices with large heat power and high heat flux.

Liquid metal spring： oscillating coalescence and ejection of contacting liquid metal droplets

与相当高的表面紧张，房间温度液体金属可以与常规液体不能拥有的意外行为继承。这里，我们经由高速度的照相机揭示了液体金属微滴的结合和喷射现象。当轻轻地联系时，它试验性地被发现那(而非碰撞) 有相同尺寸的二金属微滴一起在 NaOH 答案，震荡的结合将发生它就像在接口以后的春天一样的跑破裂并且形成毛状的波浪。为有显然不同的直径的二金属微滴，结合导致相当不平常的喷射现象。大微滴将咽下小的部分然后逐出另一小得多的微滴。如此的现象在金属微滴上为电的双层的存在提供一条直接证据。影响行为的动力学液体通过从记录电影，和液体金属微滴之间的基本差别处理图象被确定，水微滴的被澄清。与事件有关的理论机制 preliminarily 被解释。发现的礼品使液体金属微滴的基本理解清醒，它也建议使用如此的基本效果描绘粘性，表面紧张，金属液体的电的双层和微滴形成的潜在的价值。

Flexible liquid metal coil prepared for electromagnetic energy harvesting and wireless charging

This paper reported a study on a flexible liquid metal coil (LMC) for electromagnetic collection from the transmission line for self-powered sensor and electromagnetic generation for wireless charging of cellular telephone. The room temperature liquid metal of Galinstan was perfused to elastic silicone tube, which is then terminated with galliumplated copper wire. The asprepared liquid metal wire can sustain stretching, twisting, and bending with large deformation, and has a good electrical contact stability with the external circuit. The LMC based magnetic energy harvester was then designed and demonstrated to collect the magnetic field energy induced by a wire carrying alternating current. The power of 260 mW was obtained for the wire carrying current of 10 A. The flexible toroidal inductor was fabricated and tested for magnetic energy harvesting. The flexible spiralshaped LMC was also designed and demonstrated to power cellular telephone through wireless charging. The present study opens the way for further applications of elastic LMC in electromagnetic energy harvesting and charging.

Nanocellulose-based reusable liquid metal printed electronics fabricated by evaporation-induced transfer printing

Reusable electronics have received widespread attention and are urgently needed. Here, nanocellulosebased liquid metal(NC-LM) printed circuit has been fabricated by the evaporation-induced transfer printing technology. In this way, the liquid metal pattern is embedded into the nanocellulose membrane, which is beneficial for the stability of the circuit during use. Besides, the NC-LM circuit is ultrathin with just tens of microns. In particular, the finished product is environmentally friendly because it can be completely dissolved by water, and both the liquid metal ink and the nanocellulose membrane can be easily recollected and reused, thereby reducing waste and pollution to the environment. Several examples of flexible circuits have been designed to evaluate their performance. The mechanism of evaporation-induced transfer printing technology involves the deposition, aggregation, and coverage tightly of the nanosized cellulose fibrils as the water evaporated. This study provides an economical and environmentally friendly way for the fabrication of renewable flexible electronics.