Application Of Expert Systems In Analytical And Environmental Chemistry

Expert systems are knowledge based computer programs that offer the possibility of combining theories with heuristic expertise, and are therefore capable of solving domain-specific problems. However, little is known about how human knowledge can be effectively and precisely transferred into computer programs. In addition, the lack of a seamless man-machine interface also causes reduced general acceptance of expert systems. In this thesis, the process of knowledge acquisition and the role of the user interface in expert systems are investigated. Results are presented that describe the development of two prototypic expert systems: SPILLexpert and GSMSdiagnosis.;The knowledge domain matrix (KDM) is an alternative knowledge encoding mechanism that provides a causal knowledge model to be followed in the phases of knowledge extraction and interpretation. The results from the causal analysis are arranged into knowledge tables from which representation to a computer data structure, in this work production rules can be easily achieved. The KDM approach is flexible and effective in the subsequent development phases when the knowledge base is under frequent modification and/or expansion. Knowledge bases developed in this way are portable and can be readily transferred to other expert system shells.;The ACexpert graphical user interface was developed in the Microsoft Windows 3.1 environment. It provides an intuitive access to these systems through the use of graphics and pull down menus, which can be activated by either point-and-click or key stroke. This user interface has been implemented in both the SPILLexpert and GCMSdiagnosis programs.;SPILLexpert is the first expert system application of its kind developed to assist in the response to chemical spills. The importance of this work is two fold. First, an expert system holding heuristics is interfaced with a database structure that retains factual information. Second, the finished program provides a systematic and integrated approach to the development of the most appropriate response to be chosen following an environmental emergency.;GCMSdiagnosis is a diagnostic expert system for trouble-shooting operational problems with the quadrupole ion-trap GC-MS instrument. This work demonstrates the possibility of developing portable expert systems to enhance the \u27intelligence\u27 of modern analytical instruments

Solvatochromic Parameters of the Binary Mixtures of Imidazolium Chloride Ionic Liquid Plus Molecular Solvent

Imidazolium-based chloride ionic liquids (ILs) have exhibited remarkable performance in several important applications such as biomass dissolution and extraction, but their large viscosity is a non-negligible problem. Adding molecular co-solvents into chloride ILs is effective in reducing viscosity; nevertheless, understanding of the accompanied change of thermodynamic polarity is quite few. Therefore, in this work we reported three Kamlet-Taft solvatochromic parameters, including dipolarity/polarizability π*), hydrogen-bond acidity (α) and hydrogen-bond basicity (β), for the binary mixtures of several imidazolium-based chloride ILs plus either dipolar protic solvents (water and methanol) or dipolar aprotic solvents (dimethyl sulfoxide, N,N-dimethylformamide and acetonitrile). The results demonstrated that those parameters could be altered by the structure of IL and type of co-solvent owing to the solute-solvent and solvent-solvent interactions. The structure of alkyl chain of cation had considerable impact on the π* variation of IL aqueous solution against IL concentration but hardly affected other mixtures. Moreover, remarkable preferential solvation of probes was observed for β and α in the mixtures of IL and dipolar aprotic co-solvents, whereas the hydrogen-bond interactions between IL and dipolar protic co-solvent enabled the preferential solvation to be alleviated and resulted in more linear variation of β and α against the molar fraction of IL. The results not only contribute to a better understanding of the effect of co-solvent on imidazolium-based chloride ILs, but also are instructive for improving the thermodynamic performance of IL-based applications via providing IL+co-solvent mixtures with desirable physicochemical properties

LRRK2 in Parkinson's disease and dementia with Lewy bodies

BACKGROUND: Mutations in LRRK2 encoding leucine-rich repeat kinase 2 are thus far the most frequent genetic cause associated with autosomal dominant and idiopathic Parkinson's disease (PD). To examine whether LRRK2 is directly associated with neuropathology of PD and other related disorders, we analyzed LRRK2 in brains of patients affected by PD and dementia with Lewy bodies (DLB) using highly specific antibodies to LRRK2. RESULTS: We demonstrated that anti-LRRK2 antibodies strongly labelled brainstem and cortical Lewy bodies, the pathological hallmarks of PD and DLB, respectively. In addition, anti-LRRK2 also labelled brain vasculature, axons, and neuronal cell bodies. Interestingly, the immunocytochemical profile of LRRK2 varied with different antibodies depending upon specific antigenic sites along the LRRK2 protein. All anti-LRRK2 antibodies tested that were raised against various regions of LRRK2, were found to be immunoreactive to recombinant LRRK2 on Western blots. However, only the antibodies raised against the N-terminal and C-terminal regions of LRRK2, but not the regions containing folded protein domains, were positive in immunolabeling of Lewy bodies, suggesting a differential exposure of specific antigenic sites of LRRK2 on tissue sections. CONCLUSION: We conclude that LRRK2 is a component of Lewy bodies in both PD and DLB, and therefore plays an important role in the Lewy body formation and disease pathogenesis. Information on the cellular localization of LRRK2 under normal and pathological conditions will deepen our understanding of its functions and molecular pathways relevant to the progression of PD and related disorders

Automatic Process Mineralogy Based on Gold Ore Core

This is an article in the field of process mineralogy. A quartz vein type gold deposit in Shandong has a gold grade of 2.51 g/t. In order to further develop the deposit and study the beneficiation process, the process mineralogy of the mineral was carried out. The technical methods involved in this study include multi-element chemical analysis, chemical phase analysis, optical microscope identification, X-ray diffraction (XRD) analysis, automatic quantitative mineral analysis (BPMA), scanning electron microscope energy spectrometer (SEM-EDS) analysis, etc. The results show that: (1) most of the gold minerals in the ore are silver-gold, and a small amounts of gold, silver and natural gold are occasionally found; (2) The embedding relationship between gold minerals and sulfides such as pyrite in the ore is very close. Pyrite is the main carrier mineral of gold minerals, and the proportion of single and exposed gold in the ore is high, which is 58.96%. The proportion of gold encapsulated in sulfides such as pyrite is 39.84%, and the proportion of gold encapsulated in gangue minerals is 1.20%; (3) The particle size distribution of gold minerals in the ore is uneven, and the overall particle size is relatively fine. Gold particles with a particle size larger than 0.020 mm can be seen in the ore, with an occupancy rate of 22.08%. Gold minerals with a particle size less than 0.020 mm have an occupancy rate of 77.92%, with an occupancy rate of 24.83% for micro gold minerals with a particle size less than 0.005 mm and 0.35% for sub micron sized gold minerals with a particle size less than 0.001 mm

10-qubit entanglement and parallel logic operations with a superconducting circuit

Here we report on the production and tomography of genuinely entangled Greenberger-Horne-Zeilinger states with up to 10 qubits connecting to a bus resonator in a superconducting circuit, where the resonator-mediated qubit-qubit interactions are used to controllably entangle multiple qubits and to operate on different pairs of qubits in parallel. The resulting 10-qubit density matrix is unambiguously probed, with a fidelity of $0.668 \pm 0.025$. Our results demonstrate the largest entanglement created so far in solid-state architectures, and pave the way to large-scale quantum computation.Comment: Revised version with 16 pages, 13 figures, and 2 table

Photoacoustic computed tomography without accurate ultrasonic transducer responses

Conventional photoacoustic computed tomography (PACT) image reconstruction methods assume that the object and surrounding medium are described by a constant speed-of-sound (SOS) value. In order to accurately recover fine structures, SOS heterogeneities should be quantified and compensated for during PACT reconstruction. To address this problem, several groups have proposed hybrid systems that combine PACT with ultrasound computed tomography (USCT). In such systems, a SOS map is reconstructed first via USCT. Consequently, this SOS map is employed to inform the PACT reconstruction method. Additionally, the SOS map can provide structural information regarding tissue, which is complementary to the functional information from the PACT image. We propose a paradigm shift in the way that images are reconstructed in hybrid PACT-USCT imaging. Inspired by our observation that information about the SOS distribution is encoded in PACT measurements, we propose to jointly reconstruct the absorbed optical energy density and SOS distributions from a combined set of USCT and PACT measurements, thereby reducing the two reconstruction problems into one. This innovative approach has several advantages over conventional approaches in which PACT and USCT images are reconstructed independently: (1) Variations in the SOS will automatically be accounted for, optimizing PACT image quality; (2) The reconstructed PACT and USCT images will possess minimal systematic artifacts because errors in the imaging models will be optimally balanced during the joint reconstruction; (3) Due to the exploitation of information regarding the SOS distribution in the full-view PACT data, our approach will permit high-resolution reconstruction of the SOS distribution from sparse array data