Preparation and Ignition Properties of Tantalum Nitride Thin-Film Energy Transducers

Tantalum nitride (TaN) has excellent electrical properties that can be used as an energy transducer in the ignition field. In this study, TaN film transducers with different bridge parameters were designed and fabricated in an attempt to reduce its energy consumption. The ignition sensitivity of the film transducers was tested using the Langley method. The results revealed that the ignition voltage is the lowest when the thickness of the film is 0.9 µm. If the thickness and length of the bridge film are fixed, the ignition voltage of the transducer first decreases and then increases with the width of the bridge film increases. When the thickness and width of the bridge film are fixed, the ignition voltage of the transducer is first decrease and then increase with the length of the bridge film increases. We also evaluated the ignition mechanism of TaN film transducers. By comparing the performance of TaN, semiconductor bridge (SCB), and nickel–chromium (Ni–Cr) film transducers, the TaN and SCB transducers are proven to have similar ignition performances, which are better than the Ni–Cr transducer. The negative temperature coefficient of TaN and the positive feedback after the initial electrothermal ignition promoted the growth and strengthening of plasma in the bridge film, allowing the medicament to ignite quickly. When the feasibility of the process and the influence of the bridge film parameters on ignition sensitivity are considered, the preferred design parameters of the transducer are a thickness of 0.9 µm and a bridge film size of 0.3 mm×0.3 mm. This study shows that TaN can be utilized as a high-performance transducer.

A Fully Integrated AC-DC Converter in 1 V CMOS for Electrostatic Vibration Energy Transducer with an Open Circuit Voltage of 10 V

This paper proposes an AC-DC converter for electrostatic vibration energy harvesting. The converter is composed of a CMOS full bridge rectifier and a CMOS shunt regulator. Even with 1 V CMOS, the open circuit voltage of the energy transducer can be as high as 10 V and beyond. Bandgap reference (BGR) inputs a regulated voltage, which is controlled by the output voltage of the BGR. Built-in power-on reset is introduced, which can minimize the silicon area and power to function normally found upon start-up. The AC-DC converter was fabricated with a 65 nm low-Vt 1 V CMOS with 0.081 mm2. 1 V regulation was measured successfully at 20–70 °C with a power conversion efficiency of 43%.

A Fully Integrated Clocked AC-DC Charge Pump for Mignetostrictive Vibration Energy Harvesting

This paper describes a clocked AC-DC charge pump to enable full integration of power converters into a sensor or radio frequency (RF) chip even with low open circuit voltage magnetostrictive vibration energy transducer operating at a low resonant frequency of 10 Hz to 1 kHz. The frequency of the clock to drive an AC-DC charge pump was up-converted with an on-chip oscillator to increase output power of the charge pump without significantly increasing the circuit area. A model of the system including the charge pump and vibration energy transducer is shown. It was validated by HSPICE simulation and measured, resulting in a prototype chip with an area of 0.11 mm2 fabricated in a 65 nm 1 V CMOS process. The fabricated charge pump was also measured together with a magnetostrictive transducer. The charge pump converted the power from the transducer to an output power of 4.2 μW at an output voltage of 2.0 V. The output power varied below 3% over a wide input frequency of 10 Hz to 100 kHz, which suggests that universal design of the clocked AC-DC charge pump can be used for transducers with different resonant frequencies. In a low-input voltage region below 0.8 V, the proposed circuit has higher output power compared with the conventional circuits.

Concurrent unity power factor and constant mutual flux control for PMSG-WT MPPT

In this paper, a new concurrent unity power factor and constant stator flux linkage (UPF-CFL) control is presented. The main goal of this technique is to introduce the Permanent Magnet Synchronous Generator (PMSG) as an optimal wind energy transducer. The handled generator load angle and back EMF control achieve the optimum requirements for wind applications namely Maximum Power Point Tracking (MPPT). To do this, both UPF and CFL are integrated into one control methodology to obtain the advantages of each one. While the first well utilizes the apparent power increasing the generator side converter capability, the second protects the generator against magnetic saturation to enable higher speed operation. Mathematical model based on constant current fed equivalent circuit is presented taking the constraints of each individual control algorithm into account. The concurrent performance characteristics are presented and compared with each of concurrent separated algorithm characteristics for assessments. The control technique is implemented and finally, simulation testing is provided for evaluation.

Melanin, from an Evolutionary Remnant to the Myeloid Lineage Cell’s Main Energy Source. The Unsuspected Intrinsic Property of Melanin to Dissociate the Molecule from Water. Possible Implications in the Context of Acute Leukemias

Melanin is one of the most stable substances known. The study of the ink bags of fossilized squid that died 160 million years ago has found it in good condition. Its extraordinary stability is what had prevented, to date; assign a relevant role in biology. Sir Everard Holmes’ proposal in London; in the eighteenth century, about the role of melanin as a simple sunscreen, it has permeated to this day, especially among dermatologists. Despite the unique physical–chemical qualities of melanin, its biological role as a simple sunscreen that protects us from the dangerous UV rays remained immutable. Our circumstantial discovery during an observational study that lasted 12 years (1990–2002) and which included the ophthalmologic studies of 6000 patients, about the relationship between the vessels of the optic nerve and the three main causes of blindness (Macular degeneration, diabetes, and glaucoma) allowed us to discern the unexpected and surprising true role of melanin in Biology as an energy transducer. The unsuspected intrinsic property of melanin to transform light into chemical energy through water dissociation, like chlorophyll in plants; opens a new era in Biology and therefore in Medicine. And Acute Leukemias are no exception.

TonB dependent uptake of β-lactam antibiotics in the opportunistic human pathogen Stenotrophomonas maltophilia

The β-lactam antibiotic ceftazidime is one of only a handful of drugs with proven clinical efficacy against the opportunistic human pathogen Stenotrophomonas maltophilia, Here, we show that mutations in the energy transducer TonB, encoded by smlt0009 in S. maltophilia, confer ceftazidime resistance. This breaks the dogma that β-lactams enter Gram-negative bacteria only by passive diffusion through outer membrane porins. By confirming cross-resistance of Smlt0009 mutants with a siderophore-conjugated lactivicin antibiotic, we reveal that attempts to improve penetration of antimicrobials into Gram negative bacteria by conjugating them with TonB substrates is likely to select β-lactam resistance in S. maltophilia, increasing its clinical threat. Furthermore, we show that S. maltophilia clinical isolates that have an Smlt0009 mutation already exist. Remarkably, therefore, β-lactam use is already eroding the potential utility of currently experimental siderophore-conjugated antimicrobials against this species.