Investigation of Polarity Reversal of Bilayer AlN/ScAlN Films and Its Influence on Film Bulk Acoustic Resonators.

Polarity is one of the key properties that affect the functionality of piezoelectric materials. For typical piezoelectric materials, aluminum nitride (AlN) and scandium-doped aluminum nitride (ScAlN), the polarity of the films will affect the electromechanical performance of their acoustic devices. Here, metal organic chemical vapor deposition (MOCVD) and physical vapor deposition (PVD) are used to grow an AlN seed layer on a silicon substrate, and then use PVD to grow ScAlN on the AlN layer.

Enhancement of Quality Factors in a 6.5 GHz Resonator Using Mo/SiC Composite Microstructures.

This study addresses the critical challenge of lateral acoustic wave energy leakage in high-frequency film bulk acoustic resonators (FBARs) and elucidates the reflection mechanism of acoustic waves at acoustic reflection boundaries. Based on the theory of acoustic impedance mismatch, a novel Mo/SiC composite microstructure is designed to strategically establish multiple acoustic reflection boundaries along the lateral acoustic wave leakage paths. Finite element simulations reveal that SiC microstructures effectively suppress vibration amplitudes in non-resonant regions, thereby preventing acoustic wave leakage.

Chemical control of colloidal self-assembly driven by the electrosolvation force.

Self-assembly of matter in solution generally relies on attractive interactions that overcome entropy and drive the formation of higher-order molecular and particulate structures. Such interactions are central to a variety of molecular processes, e.g.

Boosting Performance of SAW Resonator via AlN/ScAlN Composite Films and Dual Reflectors.

Surface acoustic wave (SAW) resonators based on aluminum nitride (AlN)/scandium-doped AlN (ScAlN) composite thin films with dual reflection structures demonstrate substantial improvement in acoustic performance. In this work, the factors affecting the final electrical performance of SAW are analyzed from the aspects of piezoelectric thin film, device structure design, and fabrication process. AlN/ScAlN composite films can effectively solve the problem of abnormal grains of ScAlN, improve the crystal orientation, and reduce the intrinsic loss and etching defects.

14.85 µW Analog Front-End for Photoplethysmography Acquisition with 142-dBΩ Gain and 64.2-pA Noise.

A low-power, high-gain, and low-noise analog front-end (AFE) for wearable photoplethysmography (PPG) acquisition systems is designed and fabricated in a 0.35 μm CMOS process. A high transimpedance gain of 142 dBΩ and a low input-referred noise of only 64.

Effect of KNDC1 overexpression on the senescence of human umbilical vein endothelial cells.

Kinase non-catalytic C-lobe domain containing 1 (KNDC1) exists in dendrites, guanine nucleotide exchange factor complexes and neuronal cell bodies as a putative protein‑protein interaction module that regulates a number of signaling pathways. Previous studies have demonstrated that the knockdown of KNDC1 delays human umbilical vein endothelial cell (HUVEC) senescence. However, the effect of KNDC1 overexpression on HUVEC function remains unclear.

A low-power high-sensitivity analog front-end for PPG sensor.

This paper presents a low-power analog front-end (AFE) photoplethysmography (PPG) sensor fabricated in 0.35 μm CMOS process. The AFE amplifies the weak photocurrent from the photodiode (PD) and converts it to a strong voltage at the output.

Monolayer MoS2-Graphene Hybrid Aerogels with Controllable Porosity for Lithium-Ion Batteries with High Reversible Capacity.

Monolayer MoS2 nanosheets (NSs) are promising anode materials for lithium-ion batteries because all redox reactions take place at the surface without lithium-ion diffusion limit. However, the expanded band gap of monolayer MoS2 NSs (∼1.8 eV) compared to their bulk counterparts (∼1.

[Yunchang Capsule in treatment of functional constipation: a randomized, double-blinded controlled, multicenter trial].

Background: Although there are some Chinese herbal medicines in treatment of constipation, but no multi-center randomized controlled trials have been carried out to prove their effectiveness.

Objective: To evaluate the safety and efficacy of Yunchang Capsule in treatment of functional constipation with deficiency of both qi and yin and internal accumulation of poisonous pathogenic factors syndrome, and to explore the clinical dosage.

Design, Setting, Participants And Interventions: A randomized, double-blinded controlled, multicenter trial was conducted.

Beneficial effects of oolong tea consumption on diet-induced overweight and obese subjects.

Objective: To determine the anti-obesity effects of oolong tea on diet-induced overweight or obesity.

Methods: A total of 8 g of oolong tea a day for 6 weeks was ingested by 102 diet-induced overweight or obese subjects. The body fat level of the subjects was determined at the same time by taking body weight, height and waist measurements.

[Exploration on essence of spleen-kidney deficiency in middle-aged patients].

Objective: To explore the essence of Spleen-Kidney Deficiency in middle-aged patients.

Methods: Investigation was carried out in 773 cases of 50-69 years old to assay 34 parameters in them, including blood lipid, oxidation and anti-oxidation related substance, sex hormone, liver and renal function, immune function, blood routine, blood pressure and lung vital capacity, etc.

Results: Spleen Deficiency Syndrome is closely related with lipid metabolism disorder; Kidney-Qi Deficiency Syndrome is closely related with hypoimmune function; Kidney-Yin Deficiency Syndrome is closely related with lipid metabolism disorder and hypertension, and Kidney Yang Deficiency is closely related with weakness of anti-oxidation capacity, hypoimmunity, the internal environment disorder of sex hormone and aging, manifested as multiple functions abating.