Instrumental Chemistry

Established methods for characterization of tissue and diagnostics, for example histochemistry, magnetic resonance imaging (MRI), X-ray tomography, or positron emission tomography (PET), are mostly not suitable for intra-operative use. However, there is a clear need for an intra-operative diagnostics especially to identify the borderline between normal and tumor tissue. Currently, vibrational spectroscopy techniques (both Raman and infrared) complement the standard methods for tissue diagnostics. Vibrational spectroscopy has the potential for intra-operative use, because it can provide a biochemically based profile of tissue in real time and without requiring additional contrast agents, which may perturb the tissue under investigation. In addition, no electric potential needs to be applied, and the measurements are not affected by electromagnetic fields. Currently, promising approaches include Raman fiber techniques and nonlinear Raman spectroscopy. Infrared spectroscopy is also being used to examine freshly resected tissue ex vivo in the operating theater. The immense volume of information contained in Raman and infrared spectra requires multivariate analysis to extract relevant information to distinguish different types of tissue. The promise and limitations of vibrational spectroscopy methods as intra-operative tools are surveyed in this review.

An overview of recent advances in the field of analytical laser atomic spectroscopy will be discussed, in particular the laser's use as a light source in atomic absorption spectroscopy, as an excitation source in laser atomic fluorescence and laser enhanced ionization spectroscopy, as a method of solid sample introduction, and as a diagnostic tool. Selected current research in these fields will be highlighted together with their results.

Established methods for characterization of tissue and diagnostics, for example histochemistry, magnetic resonance imaging (MRI), X-ray tomography, or positron emission tomography (PET), are mostly not suitable for intra-operative use. However, there is a clear need for an intra-operative diagnostics especially to identify the borderline between normal and tumor tissue. Currently, vibrational spectroscopy techniques (both Raman and infrared) complement the standard methods for tissue diagnostics. Vibrational spectroscopy has the potential for intra-operative use, because it can provide a biochemically based profile of tissue in real time and without requiring additional contrast agents, which may perturb the tissue under investigation. In addition, no electric potential needs to be applied, and the measurements are not affected by electromagnetic fields. Currently, promising approaches include Raman fiber techniques and nonlinear Raman spectroscopy. Infrared spectroscopy is also being used to examine freshly resected tissue ex vivo in the operating theater. The immense volume of information contained in Raman and infrared spectra requires multivariate analysis to extract relevant information to distinguish different types of tissue. The promise and limitations of vibrational spectroscopy methods as intra-operative tools are surveyed in this review.

Reason for IR spectra * polar nature * dipole moment * partial charges * Absorption of IR radiation * Electric f i eld of IR radiations excite the vibrational energy of molecule at different rate of vibration * Change in dipole moment & hence IR active * close packed absorption bands FINGERPRINT REGION • organic molecules have a lot of C-C and C-H bonds within their structure • spectra obtained will have peaks in the 1400 cm -1 to 800 cm -1 range • this is referred to as the "fingerprint" region • the pattern obtained is characteristic of a particular compound the frequency of any absorption is also affected by adjoining atoms or groups.

IR spectra is used to identify functional groups
IR region extends from wave number of 600 cm-1 to 4000 cm-1
IR radiations is not energetic to excite the electron to higher level but can bring about changes in vibrational motions.

Vibrational motion in a molecule depends on
1) Bond strength
2) mass of atom

In polyetheracrylat (PEA) production, it is important to monitor three process parameters in order to assure a high quality of the final product: hydroxyl (OH) number, viscosity and acidity (acid number). Due to the high resolution and high sensitivity, it has been shown in the past that the Fourier transform near infrared (FTNIR) process spectrum measurements can be used to obtain spectra with precise content information about these process parameters. In order to perform an automatic supervision and to reduce the (off-line, laboratory) analysis effort of experts and operators of these substances, chemometric quantification models have to be used. In this paper, we investigate the usage of a specific type of fuzzy systems, so-called Takagi-Sugeno fuzzy systems, for calibrating the chemometric models. This type of model architecture supports the usage of piecewise local linear predictors, being able to model flexibly different degrees of non-linearities implicitly contained in the mapping between NIR spectra and reference values. The training of these models is conducted by an evolving clustering method (adding new local linear models on demand) and a local (weighted) least squares estimation of the consequent parameters, and connected with a wavelength (dimensionality) reduction mechanism. Results on a concrete data set show that it can outperform state-ofthe-art calibration methods as well as support vector regression as alternative non-linear model.

In polyetheracrylat (PEA) production, it is important to monitor three process parameters in order to assure a high quality of the final product: hydroxyl (OH) number, viscosity and acidity (acid number). Due to the high resolution and high sensitivity, it has been shown in the past that the Fourier transform near infrared (FTNIR) process spectrum measurements can be used to obtain spectra with precise content information about these process parameters. In order to perform an automatic supervision and to reduce the (off-line, laboratory) analysis effort of experts and operators of these substances, chemometric quantification models have to be used. In this paper, we investigate the usage of a specific type of fuzzy systems, so-called Takagi-Sugeno fuzzy systems, for calibrating the chemometric models. This type of model architecture supports the usage of piecewise local linear predictors, being able to model flexibly different degrees of non-linearities implicitly contained in the mapping between NIR spectra and reference values. The training of these models is conducted by an evolving clustering method (adding new local linear models on demand) and a local (weighted) least squares estimation of the consequent parameters, and connected with a wavelength (dimensionality) reduction mechanism. Results on a concrete data set show that it can outperform state-ofthe-art calibration methods as well as support vector regression as alternative non-linear model.

Spektroskopi massa atau spektrometer massa sebagai suatu instrumen yang dapat menyeleksi molekul-molekul gas bermuatan berdasarkan massa atau beratnya. Teknik ini tidak dapat dilakukan dengan spektroskopi akan tetapi nama spektroskopi dipilih disebabkan persamaannya dengan pencatat fotografi dan spektrum garis optik. Umumnya spektrum massa diperoleh dengan mengubah senyawa suatu sampel menjadi ion-ion yang bergerak cepat yang dipisahkan berdasarkan perbandingan massa terhadap muatan. Proses ionisasi menghasilkan partikel-partikel bermuatan positif, dimana massa terdistribusi adalah spesifik terhadap senyawa induk. Selain untuk penentuan struktur molekul, spektrum massa dipakai untuk penentuan analisis kuantitatif. Jika didapat data IR dan NMR yang cukup lengkap, maka MS ini dapat digunakan untuk konfirmasi dengan memperhatikan bobot molekul dan kemungkinan rumus strukturnya.

Future climate change, impacts and costs • There is a high degree of uncertainty in the future projections of temperature and rainfall arising from climate change in Ethiopia. While temperatures will rise, the future level is uncertain, with the projections indicating a 0.5°C to 2°C increase by the 2050s relative to today. There is greater uncertainty as to whether rainfall will increase or decrease and the projections indicate a change in national annual average rainfall from-25% to +30% by the 2050s. • Future climate change could have significant economic impacts. Under some extreme scenarios the impact of climate change on all sectors could reduce GDP by 10% or more by 2050. This potential decrease in GDP could impact Ethiopia's ambition to reach middle-income status by 2025.

Almost all developing countries satisfy their energy requirements from firewood. In Ethiopia majority of the rural population relies on biomass energy sources for every energy necessities. Fuelwood accounts for about 78 % of the total energy needs, whereas animal dung and crop residue share 12 % and nine percent, respectively. Almost all of the firewoods are collected from natural forests and few of them from homestead trees. Chronic drought, land degradation, and loss of soil fertility that are positively correlated with low livestock and crop productivity are extensions of deforestation for firewood. Heavy dependency on biomass fuel in Ethiopia has resulted in fast deforestation, desertification, climate change, global warming and finally decrease in agricultural productivity. Therefore the adoption of biogas technologies has great potentials to supply low-cost energy and results in less dependency on firewood. To improve such adverse socioeconomic and ecological costs, interventions like improved biogas technologies, raising community awareness on deforestation, and utilization of alternative energy technologies are recommended to conserve natural forests.

Most developing countries depend on solid biomass for household cooking energy with daunting problems to the inhabitants and the environment. This is the case in Maroua where dwindling fuel wood supply has resulted to energy scarcity in residential households pushing them into hardship, untold sufferings, and rampant deforestation. The goal of this study was to critically examine the sources of household cooking energy, analyze the new energy efficient stoves technology introduced as a suitable alternative and make recommendations. Three hundred structured household questionnaires were administered to some groups representative of the population. Some formal semi-structured interviews were administered to some stake holders in this domain. The data was analyzed using the SPSS. Systematic sampling technique and ethnographic observations revealed that the most frequently used household energy sources are wood and charcoal, though 80% of households use more than one source. Because of the plight of these traditional energy sources, a switch to more energy efficient stoves as a suitable alternative is ongoing. The study revealed that socio-cultural factors seriously affect the adoption of energy efficient Original Research Article

Laser-induced breakdown spectroscopy (LIBS) has gained great attention over the past two decades due to its many advantages, such as needless sample preparation, capability of remote measurement and fast multielement simultaneous analysis. However, because of its inherent uncertainty features of plasma, it is still a big challenge for LIBS community worldwide to realize high sensitivity and accurate quantitative analysis. Currently, many chemometric analytical methods have been applied to LIBS calibration analysis, including univariate regression, multivariate regression, principal component regression (PCR), partial least squares regression (PLSR) and so on. In addition, appropriate sample and spectral pretreatment can effectively improve the analytical performance (i.e., limit of detection (LOD), accuracy and repeatability) of LIBS. In this chapter, we briefly summarize the progress of these calibration methods and their applications on LIBS and provide our recommendations.

This study examines the energy-consumption patt ern in the Kilimanjaro Region in the context of the energy-switch principle and its potential contribution to reduction of deforestation and carbon dioxide emission. Such information will be useful in designing an energy-improvement strategy on emissions reduction linked to a carbon-credit-earning scheme, preferably through the United Nations Development Program (UNDP) "Millennium Development Goal Carbon Initiative," and other carbon markets. The results show that the preferred energy source is fi rewood, and a majority of respondents are still using 3-stone stoves. Wood-saving stoves are reducing fi rewood consumption and carbon dioxide emission by 51%, which is an opportunity to contribute to combating deforestation, land degradation, and carbon dioxide (CO 2) emission and benefi t from the Carbon Initiative. However, considering the high transaction and distribution costs of energy-saving technologies in Tanzania, this opportunity will only be meaningful if the government removed such constraints.

• A Mass Spectrometer analyses the relative molecular masses of an organic molecule and its fragments • A Mass Spectrometer works by a five stage process Vapourisation-The organic molecule is turned into a gas so it can pass through the Mass Spectrometer Ionisation-The organic molecule is bombarded by electrons causing it to fragment and become ionised Acceleration-The ions pass through a metal plate to accelerate them through the vacuum in the Mass Spectrometer Deflection-A high powered electromagnet, alters the projectary of the ions based on the m/z ratio desired Detection-The ions are detected on a sensor and form a digital or hard copy of a mass spectrum • The system is kept under a vacuum so atoms don't interfer with the result/movement of the ions