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A manual SPME method is presented for the analysis of organic compounds in industrial wastewater. 24 compounds commonly found in the wastewater of a chemical plant in northern Germany have been selected as reference compounds. Precision, linearity, and detection limits have been determined. Moreover, the effect of methanol content, pH value, salt content, and an excess of compounds on the extraction process have been studied. Several compounds have been investigated for their applicability as internal standards to quantify the compounds of interest. Since the method will later be transferred to a fully automated SPME-GC system, which will be operated directly on-site at an industrial wastewater purification plant, special attention has been paid to the analysis of real wastewater samples. In this context, the fibre stability has been studied by performing 53 extraction/desorption cycles from one wastewater sample. Neither a decrease in fibre performance nor in precision has been observed indicating that the proposed method is suitable for the analysis of real wastewater. Entwicklung einer SPME-GC-Methode fur die Bestimmung von organischen Schadstoffen in Abwasser Es wird eine manuelle SPME-Methode zur Analyse organischer Verbindungen in industriellem Abwasser prasentiert. 24 Verbindungen, die haufig im Abwasser eines norddeutschen Chemiebetriebes vorkommen, wurden als Referenzverbindungen ausgewahlt. Prazision, Linearitat und Nachweisgrenzen der Methode wurden ermittelt. Auserdem wurde der Effekt verschiedener Parameter wie Methanolgehalt, pH-Wert, Salzgehalt und der Einflus von Uberschuskomponenten auf die Extraktion untersucht. Mehrere Verbindungen wurden im Hinblick auf ihre Anwendbarkeit als interne Standards zur Quantifizierung der Wasserinhaltsstoffe untersucht. Da die vorgestellte Methode spater auf ein vollautomatisiertes SPME-GC-System ubertragen werden soll, das direkt an einer industriellen Abwasseraufbereitungsanlage betrieben wird, wurde insbesondere die Analytik realer Abwasserproben erprobt. In diesem Zusammenhang wurde die Faserstabilitat untersucht, indem mit einer Abwasserprobe 53 Zyklen aus Extraktion und Desorption durchgefuhrt wurden. Hierbei waren weder ein Abfall der Extraktionseffizienz der Faser noch Einbusen in der Prazision zu beobachten, so das die vorgestellte Methode zur Analyse industrieller Abwasser geeignet ist.

Data on the production of the neutralK*(892) resonances at lowpt by 200 GeVK− and π− is compared with the predictions of various models based on the quark parton model of hadrons.

The production of the neutralK− (892) resonances by 200 GeVK− andπ− has been studied over the kinematic range 0.0

Measurements of the behaviour of various high-resolution silicon strip detectors with capacitive charge division have been made in a high-energy particle beam. The results are compared with an electrostatic model which calculates the charges deposited on the strips after the passage of a minimum ionizing particle. Good agreement is found and the model is used to propose a method of improving the charge-division properties of such detectors.

A search has been made for the hadronic production of charmed baryons and mesons with a large aperture forward magnetic spectrometer using 150 GeV protons originating from the CERN-SPS. A prompt electron trigger was used as a signature for charm. Upper limits at 90% confidence level have been obtained for the production of Λ c + D 0 , D 0 D + and D − : σ(Λ c ) ⩽ 8 μ b , σ( D 0 ) ⩽ 64 μ b , σ( D 0 ) b , σ( D + ) ⩽ 51 μ b and σ( D − ) ⩽ 49 μ b per nucleon, assuming linear A dependence. Systematic errors due to uncertainties in branching ratios and to model dependence of the acceptance calculation are discussed.

We have observed three unique decays of F mesons into KK π and five unique decays of D mesons into KK π using the NA11 spectrometer together with a telescope of high-resolution silicon microstrip detectors. The mass value obtained for the F meson is (1975 ± 4) MeV, the lifetime (3.2± 1.3 3..0 )×10 −13 s.

A telescope consisting of six silicon microstrip detectors achieving 5 μm spatial resolution for minimum ionizing particles has been built. The design and fabrication of the counters, electronics, and mechanical set-up is described, and first results of its performance in a 175 GeV/c beam are reported.

The joint production of ϕ mesons andπ ±,π 0,p, $$\bar p$$ ,K 0 andK ± is investigated using a sample of 600,000 inclusive ϕ meson events obtained in hadron Be interactions with incidentπ ±,p, $$\bar p$$ andK ± beams. Evidence is presented for the joint production of ϕ mesons and strange particles produced with non-strange incident beams. With incidentK ± beam the number of additional strange particles is suppressed. The results are found to be in agreement with the qualitative predictions of a parton fusion model. The comparison with the Lund model for lowp T processes is fair.

The charge collection in silicon detectors has been studied, by measuring the response to high-energy particles of a 20 μ pitch strip detector as a function of applied voltage and magnetic field. The results are well described by a simple model. The model is used to predict the spatial resolution of silicon strip detectors and to propose a detector with optimized spatial resolution.

TheA-dependence of the inclusive ϑ meson cross-section is measured using two target materials, beryllium and tantalum, in the kinematic range 0

We have measured the lifetime of charged and neutralD mesons using high resolution silicon strip detectors in the NA11 spectrometer at the CERN SPS. TheD mesons were produced in 200 GeV π− interactions. We obtain a value of $$\tau _{D^ \pm } = \left( {10.6\begin{array}{*{20}c} { + 3.6} \\ { - 2.4} \\ \end{array} } \right) \cdot 10^{ - 13} s$$ based on 28, and $$\tau _{D^0 } = \left( {3.7\begin{array}{*{20}c} { + 1.0} \\ { - 0.7} \\ \end{array} } \right) \cdot 10^{ - 13} s$$ based on 26 fully reconstructed decays for the lifetime of the charged and the neutralD meson, respectively. For the ratio $$\tau _{D^ \pm } /\tau _{D^0 }$$ we find 2.8 −0.8 +1.1 .

High precision silicon detectors, developed for the measurement of short lived particles are described, and first results on their performance are reported.

Based on the drift chamber principle a low capacity diode has been built with one large area p+n junction at the front, and p+ and n+ patterns at the rear. The capacitance of the device is only 1.5 pF at an area of 1 cm2 and a thickness of 280 μm. The energy resolution for Am α-particles is 13.5 keV, the optical sensitivity is homogeneous over the whole area, and the charge collection times lie between 10 and 300 ns.

We have measured the differential and total cross sections ofD meson production in 200 GeV π−-beryllium interactions, using a sample of 48 fully reconstructed and nearly background-freeD mesons in the decay channelsK∓π±,K∓π±π± andK∓π∓π±π±. A single electron trigger has been used to select events containing a pair of charmed particles. A vertex telescope of 6 silison microstrip detectors allowed the reconstruction of tracks of charged secondaries and the reconstruction of primary and decay vertices with high precision. The ratio of branching fractions for\(\mathop {D^0 }\limits^{( - )} \to K^ \mp \pi ^ \pm \) to\(\mathop {D^0 }\limits^{( - )} \to K^ \mp \pi ^ \mp \pi ^ \pm \pi ^ \pm \), and an upper limit for\(D^0 - \bar D^0 \) mixing are presented.

The reactions $$K^ - Be \to {}^(\bar K^) *^0 (890)X,\pi ^ - Be \to {}^(\bar K^) *^0 (890)X$$ , have been studied in a 175 GeV unseparated hadron beam in the kinematic range 0

A pressurized drift chamber is described which measured particle tracks at 10 points. For particles in a beam of low intensity, an accuracy of 23μm per point is obtained. Downstream of a target in a high-intensity beam, events are reconstructed with an accuracy of 30 μm per point.

A silicon detector telescope with 5 μm spatial resolution has been developed and successfully used to select charmed particles produced in high energy hadron collisions. A brief review of the properties and the performance of the system is given.