Comparative Study on the Macroscopic Characteristics of Gasoline and Ethanol Spray from a GDI Injector under Injection Pressures of 10 and 60 MPa.

To reduce particulate matter (PM) emissions from vehicles powered by gasoline direct injection (GDI) engines, increasing the fuel injection pressure has been one promising approach. However, a comparison of macroscopic characteristics between gasoline and ethanol from a GDI injector under an ultrahigh injection pressure of more than 50 MPa has not been reported. The experimental study presented in this paper can provide some new and valuable information about comparing and analyzing the macroscopic characteristics of gasoline and ethanol spray from a GDI injector in both front and side views under injection pressures of 10 and 60 MPa. The experimental results show that compared to ethanol, gasoline spray has a slight advantage in L S (penetration of whole spray), L C (penetration of core region of spray), θS (spray cone angle), and R I (irregularity of spray boundary) under both P I (injection pressure) = 10 MPa and P I = 60 MPa, which would promote a more homogeneous mixture of air and fuel. Furthermore, the advantage of gasoline in θS is more pronounced under P I = 60 MPa. At the end of injection, S S (area of whole spray) of gasoline is around 2% larger than ethanol, while its advantage in S C (area of core region of spray) can be around 5%. With the increase of P I from 10 to 60 MPa, a marked increase of R S (the ratio of S C to S S) and R I indicates that atomization and air-fuel mixture homogeneity can be significantly improved for both gasoline and ethanol spray. Besides, a minor revision to the Dent model helps achieve a significant improvement in the prediction accuracy of L S for both gasoline and ethanol spray under injection pressures of 10 and 60 MPa.

Implementation of Oxy-Fuel Combustion (OFC) Technology in a Gasoline Direct Injection (GDI) Engine Fueled with Gasoline-Ethanol Blends.

Nowadays, to mitigate the global warming problem, the requirement of carbon neutrality has become more urgent. Oxy-fuel combustion (OFC) has been proposed as a promising way of carbon capture and storage (CCS) to eliminate carbon dioxide (CO2) emissions. This article explores the implementation of OFC technology in a practical gasoline direct injection (GDI) engine fueled with gasoline-ethanol blends, including E0 (gasoline), E25 (25% ethanol, 75% is gasoline in mass fraction), and E50 (50% ethanol, 50% is gasoline in mass fraction). The results show that with a fixed spark timing, φCA50 (where 50% fuel is burned), of E50 and E25 is about 4.5 and 1.9° later than that of E0, respectively. Ignition delay (θF) and combustion duration (θC) can be extended with the increase of the ethanol fraction in the blended fuel. With the increase of the oxygen mass fraction (OMF) from 23.3 to 29%, equivalent brake-specific fuel consumption (BSFCE) has a benefit of 2.12, 1.65, and 1.51% for E0, E25, and E50, respectively. The corresponding increase in brake-specific oxygen consumption (BSOC) is 21.83, 22.42, and 22.58%, respectively. Meanwhile, θF, θC, and the heat release rate (HRR) are not strongly affected by the OMF. With the increase of the OMF, the increment of θF is 0.7, 1.8, and 2.2° for E0, E25, and E50, respectively. θC is only extended by 1, 1.1, and 1.4°, respectively. Besides, by increasing the intake temperature (T I) from 298 to 358 K under all of the fuel conditions, BSFCE and BSOC present slight growth trends; θF and θC are slightly reduced; in the meantime, φCA50, φPmax (crank angle of peak cylinder pressure), and the position of the HRR peak are advanced by nearly 1°.

Application of atomic force microscope in diagnosis of single cancer cells.

Changes in mechanical properties of cells are closely related to a variety of diseases. As an advanced technology on the micro/nano scale, atomic force microscopy is the most suitable tool for information acquisition of living cells in human body fluids. AFMs are able to measure and characterize the mechanical properties of cells which can be used as effective markers to distinguish between different cell types and cells in different states (benign or cancerous). Therefore, they can be employed to obtain additional information to that obtained via the traditional biochemistry methods for better identifying and diagnosing cancer cells for humans, proposing better treatment methods and prognosis, and unravelling the pathogenesis of the disease. In this report, we review the use of AFMs in cancerous tissues, organs, and cancer cells cultured in vitro to obtain cellular mechanical properties, demonstrate and summarize the results of AFMs in cancer biology, and look forward to possible future applications and the direction of development.

Fabrication of hierarchical moth-eye structures with durable superhydrophobic property for ultra-broadband visual and mid-infrared applications.

Multifunctional antireflective coatings have practical applications as important optical components in many fields, particularly for optical devices and imaging systems. However, a good antireflection application in the visible region is often unsatisfactory for mid-infrared devices, and the difficulty in obtaining multiple capabilities simultaneously is one of the main factors limiting their applications. In this work, hierarchical moth-eye structures with superhydrophobicity were fabricated via inductively coupled plasma reactive ion etching (ICP-RIE) using nanodisk-array masks, which were formed by three-beam laser interference lithography (LIL), for improving the ultra-broadband optical properties. The uniform antireflection efficiency, which was close to 1% reflectivity covering over the visible and mid-infrared wavelength range, was exhibited by the moth-eye structures with high-quality pillar arrays. Additionally, irregular nanostructures were tailored onto the top of the pillars to generate hierarchical moth-eye structures for simultaneously obtaining both the superhydrophobic and anticorrosive properties. The fabricated antireflective structures, with the features of self-cleaning and durability, have the advantage of being for long-term use in harsh environments.

Study of morphological and mechanical features of multinuclear and mononuclear SW480 cells by atomic force microscopy.

This article studies the morphological and mechanical features of multinuclear and mononuclear SW480 colon cancer cells by atomic force microscopy to understand their drug-resistance. The SW480 cells were incubated with the fullerenol concentrations of 1 mg/ml and 2 mg/ml. Morphological and mechanical features including the height, length, width, roughness, adhesion force and Young's modulus of three multinuclear cell groups and three mononuclear cell groups were imaged and analyzed. It was observed that the features of multinuclear cancer cells and mononuclear cancer cells were significantly different after the treatment with fullerenol. The experiment results indicated that the mononuclear SW480 cells were more sensitive to fullerenol than the multinuclear SW480 cells, and the multinuclear SW480 cells exhibited a stronger drug-resistance than the mononuclear SW480 cells. This work provides a guideline for the treatments of multinuclear and mononuclear cancer cells with drugs.

Compensation of the magnetic force imaging by scanning directions.

It was found that the results of magnetic force microscope (MFM) imaging were different with the probe scanning directions. This paper studied the effect of scanning directions on the MFM imaging, and a method for the distortion compensation was proposed to reduce the errors. In the study, three different scanning directions with the angles of 0°, 45° and 90° were used to measure the magnetic domain structures distributions of magnetic sample. The experimental results have shown that the scanning direction parallel to the magnetic domain structure will cause a minimum phase shift difference and lead to a structure distortion. A method for compensating the distortions was proposed. With this method, the distorted structures were corrected and the effect of scanning directions on the MFM imaging was significantly reduced. This work provides a way for the acquisition of the correct images of magnetic structures using an MFM and the improvement of imaging quality in a wide range of MFM applications.

Cleaning of contaminated MFM probes using a BOPP film and external magnetic field.

When magnetic samples are tested with a magnetic force microscope (MFM), the probe tip can inevitably be contaminated and magnetic particles are often adhered to the tip surface. The probe with magnetic contamination will seriously affect the quality of morphological and magnetic imaging. In the work, a method for the cleaning of contaminated magnetic probe tips was developed by the use of a biaxially-oriented polypropylene (BOPP) film together with an external magnet field in an MFM system. In the experiments, an MFM system was used for manipulating the tip to push into the BOPP film with a depth of 50-100nm under a magnetic field and hold for 5s, and the relationships between loading forces and separating forces were studied. The scanning electron microscope (SEM) images have shown that the use of the BOPP film together with an external magnet field is effective for the cleaning of contaminated MFM probes. This method can greatly improve the quality of magnetic imaging, prolong the service life of magnetic probes and reduce the experimental costs in many MFM applications.