Abstract: The present invention relates to a dinitroxide biradical compound of general formula (I): In formula (I), A is a carbon, an ammonium, or a phosphonium; each of A1 to A6 is a single bond, O, N, N(O), S, S(O), SO2, C(O), or a (C1-C4) alkyl chain; and Z1 and Z2 are selected from R1 and R2 in combination, so that there is always at least one R2 group that is substituted with R3 group. In Z1 and Z2, R1 is an H, an aryl, or a heteroaryl; R2 is an alkyl chain, an alkenyl chain, an alkynyl chain, a cycloalkyl, a heterocycloalkyl, an aryl, or a heteroaryl; and R3 is an alkyl chain, an alkenyl chain, an alkynyl chain, a cycloalkyl, a heterocycloalkyl, an aryl, a heteroaryl, an ether, an ester, or an azide. When Z1 and Z2 are combined together with the same carbon atom of the nitroxide ring to which they are bonded, they form a spirocycloalkyl or a spiroheterocycloalkyl, the spirocycloalkyl or the spiroheterocycloalkyl being substituted with R3.

Abstract: The invention relates to compounds of general formula (I) wherein X is C?O or SO2, M is NR2 or O, and Q1 and Q2 are nitroxide-containing radicals, and their use as a Dynamic Nuclear Polarization (DNP) agent for polarizing an NMR-active spin of a nucleus of an analyte in Nuclear Magnetic Resonance (NMR) spectroscopy.

Abstract: A method of providing a material sample in a state favorable to retaining spin polarization includes cooling a material sample from a temperature above a freezing point of the material sample down to a second temperature below the freezing point of the material sample; maintaining the sample at about the second temperature for a period of about several hours; and reducing temperature of the material sample to a third temperature lower than the second temperature to provide the material sample in a state favorable to retaining spin polarization, where the steps of cooling, maintaining and reducing are performed in the absence of an adulterant material. The method of providing a sample of pyruvic acid in a state favorable to retaining spin polarization may include cooling the sample of pyruvic acid in the absence of an adulterant material from a temperature above a freezing point of the sample of pyruvic acid down to less than about 200 Kelvin to provide the sample.

Abstract: Non aqueous solvents or mixtures for DNP NMR spectroscopy, method to prepare said solvents or mixtures and use of said solvents or mixtures The present invention concerns a method to determine the efficiency of a solvent to impregnate a sample material for use in a dynamic nuclear polarization (DNP) nuclear magnetic resonance (NMR) experiments, characterized in that the method comprising: —selecting a non-aqueous solvent, —providing a polarizing agent that is soluble in the non-aqueous solvent, —dissolving the polarizing agent in the non-aqueous solvent, —impregnating or dissolving the sample material with the non-aqueous solvent containing the polarizing agent, —performing a solid state DNP NMR experiment on the impregnated sample material, —determining a DNP enhancement factor of the DNP NMR experiment.

Abstract: The invention concerns a dinitroxide biradical compound, in which the two nitroxide units are held by a rigid linkage, of general formula (I) in which—A is a carbon, an ammonium or a phosphonium, each of A1 to A6 is selected separately from the group comprising a single bond, O, N, N(O), S, S(O), SO2, C(O), a (C1-C4) alkyl chain, Z1 and Z2 are chosen from RI and R2 in combination, such that there is always, in the combination, at least one R2 group that needs to be substituted by an R3 group, RI is an H, a (C6-C18) aryl or a (C3-C18) heteroaryl, R2 a (C1-C17) alkyl chain, a (C1-C17) alkenyl chain, a (C1-C17) alkynyl chain, a (C4-C17) cycloalkyl, a (C4-C17) heterocycloalkyl, a (C6-C18) aryl, a (C3-C18) heteroaryl, R3 is a (C1-C17) alkyl chain, a (C1-C17) alkenyl chain, a (C1-C17) alkynyl chain, a (C4-C17) cycloalkyl, a (C4-C17) heterocycloalkyl, a (C6-C18) aryl, a (C3-C18) heteroaryl, an ether —OR, an ester —C(O)O—R (in which R is any hydrocarbon radical), an azide, and in which, when Z1 and Z2 are combined to

Abstract: The invention relates to compounds of general formula (I) wherein X is C?O or SO2, M is NR2 or O, and Q1 and Q2 are nitroxide-containing radicals, and their use as a Dynamic Nuclear Polarization (DNP) agent for polarizing an NMR-active spin of a nucleus of an analyte in Nuclear Magnetic Resonance (NMR) spectroscopy.

Abstract: A method of providing a material sample in a state favorable to retaining spin polarization includes cooling a material sample from a temperature above a freezing point of the material sample down to a second temperature below the freezing point of the material sample; maintaining the sample at about the second temperature for a period of about several hours; and reducing temperature of the material sample to a third temperature lower than the second temperature to provide the material sample in a state favorable to retaining spin polarization, where the steps of cooling, maintaining and reducing are performed in the absence of an adulterant material. The method of providing a sample of pyruvic acid in a state favorable to retaining spin polarization may include cooling the sample of pyruvic acid in the absence of an adulterant material from a temperature above a freezing point of the sample of pyruvic acid down to less than about 200 Kelvin to provide the sample.

Abstract: A closed container having a single opening is sealed by a plug fabricated from a self-sealing elastomer. Before insertion, the plug is transfixed with a tube to allow air to escape as the plug is pushed into the container. The plug and tube are then inserted into a container. After the plug has been seated in the container, the tube is withdrawn, allowing the self-sealing elastomeric material to close the canal formed by the tube and to form a hermetic seal.

Abstract: Apparatus for preventing energy leakage from a transmission line treats the line as a “partially closed” vessel. A gas stream with a pressure slightly different from ambient pressure is provided to the interior of the transmission line and a conduit that allows gas to pass between the transmission line and the ambient environment is provided. The gas flow rate at the conduit is then detected and monitored. If the flow rate falls outside a predetermined threshold, an electrical energy leakage is indicated. In another embodiment, the pressure of the input gas to the transmission line is continuously checked by a pressure switch, which will detect a change in pressure if the transmission integrity is compromised and disable the energy source.