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This work presents first results of a new approach for the detection of biological contamination using the Surface Plasmon Resonance (SPR) spectroscopy. SPR sensors have been commonly employed for the detection of proteins, bacteria and chemical substances. However, only specific interactions can be detected so far that rely on specific and sensor immobilized receptor molecules. It is of importance to overcome this limitation as technical fluids like cooling lubricants, paints and varnishes often show contaminations with different strains of microorganisms. The here presented general approach will focus on a distinguished mode of action. The aim is an unspecific adsorption of bacteria and other microorganisms to differently processed metal surfaces. The processed sensor surface is characterized by means of contact angle measurements, scanning electron microscopy, and bacterial and fungal binding studies. Besides, one of the main advantages of the sensor is the usability in a multitude of liquids such as deeply contaminated emulsions and other technical fluids, providing a broad applicability of the sensor system.

Gravitational wave is predicted by Einstein’s general relativity, which conveys the information of source objects in the universe. The detection of the gravitational wave is the direct test of the theory and will be used as new tool to investigate dynamical nature of the universe. However, the effect of the gravitational wave is too tiny to be easily detected. From the first attempt utilizing resonant antenna in the 1960s, efforts of improving antenna sensitivity were continued by applying cryogenic techniques until approaching the quantum limit of sensitivity. However, by the year 2000, resonant antenna had given the way to interferometers. Large projects involving interferometers started in the 1990s, and achieved successful operations by 2010 with an accumulated extensive number of technical inventions and improvements. In this memorial year 2015, we enter the new phase of gravitational-wave detection by the forthcoming operation of the second-generation interferometers. The main focus in this paper is on how advanced techniques have been developed step by step according to scaling the arm length of the interferometer up and the history of fighting against technical noise, thermal noise, and quantum noise is presented along with the current projects, LIGO, Virgo, GEO-HF and KAGRA.

In this paper, a new unambiguous tracking technique is proposed for binary offset carrier (BOC) modulated signals. The tracking loop in this technique is based on a synthesized correlation function which has only one positive peak. For different types of BOC signal, the proposed technique employs symmetrical equivalent pulse width modulated symbols of the auxiliary signal. The theoretical false alarm and detection performance formulas are given and simulated. Theoretical and simulation results show that this technique can be a solution to removes the ambiguity completely.

During the process of steel manufacturing, the sectional dimension would be detected to tell the quality of the steel. Nowadays the main detection method is by manual operation for machine. But the results of manual detection vary greatly according to the steel placement, operation process and subjectivity of the operators. Thus manual detection is wildly inaccurate. This paper introduces a new detection method applied on steel sectional dimension based on image processing. This method collects images of the steel cross-section, and converts images to binary ones. The edge feature points are extracted from the binarization images and steel sectional dimension would be detected by the maximum entropy method. The experimental results show that using this algorithm greatly improves the accuracy of detection and achieves satisfactory results.

When the ozone keeps in state of gas, along with the increasing temperature, the decomposition rate of ozone is accelerated while the half-life of the decomposition decreases gradually, which makes a great contribution to the precise detection of the ozone concentration. This paper has probed into the decomposition law of the existed ozone in oxygen, proposing the decomposition law of ozone in air and getting access to the absorbance of the ozone, the relation curve of concentration of the ozone in temperature and air, and the coefficient of decomposition rate. New expressions of gaseous ozone concentration monitoring are given, expecting to improve the accuracy.

Norovirus is an etiologic agent of acute diarrhea, mainly through contaminated food and water. Even a low titer of virus in water or food can give rise to a significant outbreak. The purpose of this review is to provide the current status of the development of the method for norovirus concentration from different samples. Ultracentrifugation is the standard method for norovirus detection in fecal specimen or food sample, which can be applicable to even small-volume samples. Although both negatively and positively charged filters have are equally effective in handling large-volume samples, positively charged filters are superior to negative ones when preconditioning is not available in field sampling. Viruses can be concentrated by ultrafiltration based on size exclusion. It is not applicable to food samples, because they tend to clog the membranes.

In Chapter 3, coronary computed tomography angiography (CCTA) characterization and assessment of coronary plaques was discussed, but with a focus on 2D and 3D visualizations of plaques. This chapter mainly deals with the quantitative analysis of plaque features or components by CCTA with corresponding clinical significance in the diagnostic assessment of coronary artery disease (CAD). Identification of specific morphological plaque features on CCTA is of paramount importance to diagnose high-risk patients and guide effective patient management. The purpose of this chapter is to discuss the clinical value of CCTA in the diagnostic assessment of plaques with the aim of identifying vulnerable plaques, therefore, achieving the goal of predicting and preventing major adverse cardiac events.

A method for the detection of genetically modified components (GMCs) is reported for detection of GMCs in rice plants and foods using a membrane-based array. A DNA sequence as probes was immobilized on modified paper film-chips to form the sensing array surface. The target DNA from sample was amplified by polymerase chain reaction (PCR) using labeled biotin primers. The PCR products were added to the sensing surface using an automatic membrane-based array instrument (MAI). When the target DNA passed the surface, it was captured by the complementary probes. The signal was visualized with a streptavidin/alkaline phosphatase (AP) and AP color development kit. Compared to manual dot blotting, the MAI could automatically and rapidly finish several GMC types of rice detection, such as BT11, TC1507, Mon88017, and Mon89034. Stable and consistent qualitative results were acquired. The sensitivity reached 0.1%. Thus, the automatic MAI might be a valuable GMC detection tool.

Polyvinylidene fluoride (PVDF) is a new type of piezoelectric polymer material, which has a unique piezoelectric effect and has been widely used to measure vibration parameters in resent years. It is used to measure the dynamic strain of metal material induced by pulsed laser. The 2024 aluminum alloy is taken as an example. The laser signal which is received by photoelectric diode is a trigger signal of the oscillograph. Then the piezoelectric signal of PVDF piezoelectric film is collected timely. The voltage and time curve is outputted and calculated by the computer, and then the strain and time curve is received. Experimental results showed that this test method is convenient and accurately, and can detect the dynamic strain of the material timely.

Co₂P nanocomposites were successfully synthesized via a facile hydrothermal method. The microstructure, morphology and elemental composition were examined by XRD, SEM, TEM and XPS. The effects of synthesis temperature and reaction time on the sensing properties of Co₂P nanocomposites were analyzed. The Co₂P sensor at 200°C and 3 h reaction condition exhibited optimum sensitivity toward 100 ppm ethanol. In comparison with other gases, ethanol possesses good selective characteristics at optimal operating temperature of 160°C, which greatly reduce energy consumption. The above results showed that Co₂P nanocomposites have the potential application as an effective sensor for ethanol detection.